Calculating speed, time, and distance Name ______________________________
Equations: Distance
Speed = Time
Distance
Time = Speed
Distance = Speed Time
Directions: Use the equation above to answer the following questions. Show your work and include the units.
You are not going to be able to adhere to significant figures on EVERY problem, just do your best.
1. Julia drives her car with a constant speed of 92.0 km/h. How far can she travel in 3.25 hours? Givens Solving For
Equation Substitution Answer with Units
2. A police car drives with a constant speed of 116 km/h. How long will it take to travel a distance of 464
kilometers? Givens Solving For
Equation Substitution Answer with Units
3. An airplane flies 1980 km in 2.75 hours. What is its average speed in kilometers per hour? Givens Solving For
Equation Substitution Answer with Units
4. An airplane flies 1760 km in 2.75 hours. What is its average speed in kilometers per hour? Givens Solving For
Equation Substitution Answer with Units
5. A van moves with a constant speed of 52 km/h. How far can it travel in 2.25 hours? Givens Solving For
Equation Substitution Answer with Units
92 km/hr 3.25 hrs
Distance
D = T x S D = 3.25 x 92 299 km/hr
1
6. A taxi hurries with a constant speed of 96 km/h. How long will it take to travel a distance of 275km? Givens Solving For
Equation Substitution Answer with Units
7. An airplane flies with a constant speed of 840.0 km/h. How far can it travel in 1.250 hours? Givens Solving For
Equation Substitution Answer with Units
8. An airplane flies with a constant speed of 960.0 km/h. How far can it travel in 2.750 hours? Givens Solving For
Equation Substitution Answer with Units
9. An airplane flies 2200 km in 2.75 hours. What is its average speed in kilometers per hour? Givens Solving For
Equation Substitution Answer with Units
10. A train travels with a constant speed of 88.0 km/h. How far can it travel in 1.50 hours? Givens Solving For
Equation Substitution Answer with Units
11. Mike rides his bike with a constant speed of 14 km/hr. How long will he take to travel a distance of 21km? Givens Solving For
Equation Substitution Answer with Units
2
12. Nancy roller skates with a constant speed of 12.0 km/hr. How long will she take to travel a distance of
18.0 km? Givens Solving For
Equation Substitution Answer with Units
13. A van moves with a constant speed of 60.0 km/hr. How far can it travel in 1.5 hours? Givens Solving For
Equation Substitution Answer with Units
14. Noah rides his bike with a constant speed of 14 km/hr, how far can he travel in 0.50 hours? Givens Solving For
Equation Substitution Answer with Units
15. A car drives with a constant speed of 32 km/h. How long will it take to travel a distance of 96 km? Givens Solving For
Equation Substitution Answer with Units
16. A minibus drives with a constant speed of 32.0 km/hr. How far can it travel in 6.00 hours? Givens Solving For
Equation Substitution Answer with Units
17. A girl cycles for 3.00 hrs at a speed of 40.0 km/h. What distance did she travel? Givens Solving For
Equation Substitution Answer with Units
3
18. A train travels at a speed of 30.0 km/hr and travel a distance of 240 km.. How long did it take the train to
complete it’s journey? Givens Solving For
Equation Substitution Answer with Units
19. A car travels a distance of 540 km in 6.0 hours. What speed did it travel at? Givens Solving For
Equation Substitution Answer with Units
20. John is a runner. He runs the 100.0 m sprint in 10.6s. What speed did he travel at? (in m/s) Givens Solving For
Equation Substitution Answer with Units
21. A cyclist travels 20.0 km in 4.0 hrs. What speed did the cyclist cycle at? Givens Solving For
Equation Substitution Answer with Units
22. The distance between two cities is 144 km, it takes me 3.0 hours to travel between these cities. What
speed did I travel at? Givens Solving For
Equation Substitution Answer with Units
23. A coach travels from the station to the beach, a distance of 576km away in 6hrs. The coach is only allowed
to travel at a maximum speed of 90.0 km/h. Did the coach break the speed limit? Givens Solving For
Equation Substitution Answer with Units
Yes or no? (Circle One)
4
24. A bullet travels at 850 m/s. How long will it take a bullet to go 100.0 m? Givens Solving For
Equation Substitution Answer with Units
25. Lauren walks 100.0 m in 35 seconds. What must her speed have been to travel this distance? Givens Solving For
Equation Substitution Answer with Units
26. A mouse runs a distance of 2.0 meters in 15 seconds. What is its speed? Givens Solving For
Equation Substitution Answer with Units
27. Jim travelled at a speed of 18km/h for 2.0 hours. What was the distance covered? Givens Solving For
Equation Substitution Answer with Units
28. Marc was told his dinner would be ready at 6:00. He left his house at 12:00 & travelled in his car at an
average speed of 45mph to his mom’s house 300.0 miles away. Did Marc make it home in time for dinner? Givens Solving For
Equation Substitution Answer with Units
Yes or no? (Circle One)
29. A whale swims at a constant speed of 8.01 m/s for 17.0 s. What distance did it travel? Givens Solving For
Equation Substitution Answer with Units
5
30. If a car travels 400 m in 20 seconds how fast is it going? Givens Solving For
Equation Substitution Answer with Units
31. If you move 50 meters in 10 seconds, what is your speed? Givens Solving For
Equation Substitution Answer with Units
32. You arrive in my class 45 seconds after leaving math which is 90 meters away. How fast did you travel? Givens Solving For
Equation Substitution Answer with Units
33. A plane travels 395,000 meters in 9000 seconds. What was its speed? Givens Solving For
Equation Substitution Answer with Units
34. In a competition, an athlete threw a flying disk 139.0 meters through the air. While in flight, the disk
traveled at an average speed of 13.0 m/s. How long did the disk remain in the air? Givens Solving For
Equation Substitution Answer with Units
35. It takes Serina 0.25 hours to drive to school. Her route is 16 km long. What is Serina’s average speed on
her drive to school? Givens Solving For
Equation Substitution Answer with Units
6
36. A football field is about 100 m long. If it takes a person 20 seconds to run its length, how fast (what speed)
were they running? Givens Solving For
Equation Substitution Answer with Units
37. The pitcher’s mound in baseball is 85.0 m from the plate. It takes 4.0 seconds for a pitch to reach the plate.
How fast is the pitch? Givens Solving For
Equation Substitution Answer with Units
38. If you drive at 100.0 km/hr for 6.00 hours, how far will you go? Givens Solving For
Equation Substitution Answer with Units
39. If you run at 12.0 m/s for 900.0 sec, how far will you go? Givens Solving For
Equation Substitution Answer with Units
40. Every summer I drive to Michigan. It is 3900 km to get there. If I average 100 km/hr, how much time
will I spend driving? Givens Solving For
Equation Substitution Answer with Units
41. Every winter I fly home to Michigan (3900 km away). It takes 5.0 hours. What is my average speed? Givens Solving For
Equation Substitution Answer with Units
7
42. The fastest train in the world moves at 500.0 km/hr. How far will it go in 3.000 hours? Givens Solving For
Equation Substitution Answer with Units
43. How long will it take sunlight moving at 300,000 km/s to reach us? The sun is 15,000,000 km from earth. Givens Solving For
Equation Substitution Answer with Units
44. If Steve throws the football 50.0 meters in 3.01 seconds, what is the average speed of the football? Givens Solving For
Equation Substitution Answer with Units
45. If it takes Ashley 3.00s to run from the batter’s box to first base at an average speed of 6.50 m/s, what is
the distance she covers in that time? Givens Solving For
Equation Substitution Answer with Units
46. Bart ran 5000 meters from the cops and an average speed of 6.00 meters/second before he got caught.
How long did he run? Givens Solving For
Equation Substitution Answer with Units
47. Justin races his Chevy down Hwy 37 for 2560 meters in 60.0 seconds, what is his average speed? Givens Solving For
Equation Substitution Answer with Units
8
48. Mike rides his motorcycle at an average speed of 20 meters/second for 500 seconds, how far did he ride?
Givens Solving For
Equation Substitution Answer with Units
49. Sarah backstrokes at an average speed of 8.0 meters per second, how long will it take her to complete the
race of 200.0 meters length?
Givens Solving For
Equation Substitution Answer with Units
50. The distance around the earth is 21,000.0 kilometers around the earth and the earth rotates in 24.0 hrs.
How fast is it rotating? Givens Solving For
Equation Substitution Answer with Units
9
10
Name ______________________Calculating Speed, Time and Distance Answer Sheet
________1. A. 28.3 B. 299 C. 0.035
________2. A. 4.0 B. 53824 C. 0. 246
________3. A. 5440 B. 720 C. 0.0014
________4. A. 0.0016 B. 4840 C. 640
________5. A. 0.04 B. 23.1 C. 117
________6. A. 0.349 B. 2.9 C. 26400
________7. A. 672 B. 1050 C. 0.015
________8. A. 0.0029 B. 349 C. 2640
________9. A. 800 B. 6050 C. 0.0125
________10. A. 132 B. 58.7 C. 0.017
________11. A. 294 B. 1.5 C. 0.667
________12. A. 0.67 B. 1.5 C. 216
________13. A. 40 B. 90 C. 0.025
________14. A. 7.0 B. 28 C. 0.036
________15. A. 3.0 B. 0.33 C. 3072
________16. A. 5.33 B. 0.1875 C. 192
________17. A. 0.075 B. 13.3 C. 120
________18. A. 0.125 B. 7200 C. 8.0
________19. A. 0.025 B. 3240 C. 90
________20. A. 9.4 B. 1060 C. 0.106
________21. A. 5.0 B. 80 C. 0.2
________22. A. 0.02 B. 432 C. 48
________23. A. 3456 B. 96.0 C. 0.01
________24. A. 0.118 B. 85000 C. 8.5
________25. A. 0.35 B. 2.9 C. 3500
________26. A. 30 B. 7.5 C. 0.133
________27. A. 36 B. 9.0 C. 0.11
________28. A. 6.7 B. 13500 C. 0.15
________29. A. 136 B. 0.944 C. 1.06
11
________30. A. 8000 B. 20 C. 0.05
________31. A. 5.0 B. 500 C. 0.2
________32. A. 4050 B. 2.0 C. 0.5
________33. A. 43.9 B. 0.023 C. 3.6 x 109
________34. A. 0.09 B. 10.7 C. 1807
________35. A. 4.0 B. 64 C. 0.016
________36. A. 0.2 B. 5.0 C. 2000
________37. A. 21 B. 340 C. 0.047
________38. A. 16.67 B. 600 C. 0.06
________39. A. 75 B. 0.013 C. 10,800
________40. A. 39 B. 0.00128 C. 39,000
________41. A. 780 B. 19500 C. .00128
________42. A. 0.006 B. 1500 C. 166.7
________43. A. 50 B. 0.02 C. 4.5 x 1012
________44. A. 151 B. 16.6 C. 0.0602
________45. A. 2.2 B. 19.5 C. 0.46
________46. A. 833 B. 30,000 C. 0.012
________47. A. 0.23 B. 42.7 C. 153,600
________48. A. 0.04 B. 25 C. 10,000
________49. A. 0.04 B. 25 C. 1600
________50. A. 875 B. 0.001 C. 504,000
12
Name Class
Student ID
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Spee
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Grade.c
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Practice Problem Set FORCE = MASS x ACCELERATION
Equations: F=m x a a=F/m m=F/a
Plug in the given values for Force/Mass/Acceleration to solve.
Remember, mass is in kg - - force in in N (Newtons) - - acceleration is in m/s2
1. A man hits a golf ball (0.2 kg) which accelerates at a rate of 20 m/s2. What amount of force acted on the
ball?
Givens
0.2 kg, 20 m/s2
Solving For
Force
Equation
F = m x a
Substitution
F = 0.2 x 20
Answer with Units
4 N
2. You give a shopping cart a shove down the aisle. The cart is full of groceries and has a mass of 18.0 kg.
The cart accelerates at a rate of 3.0 m/s2. How much force did you exert on the cart?
Givens
Solving For
Equation
Substitution
Answer with Units
3. The wind pushes a paper cup along the sand at a beach. The cup has a mass of 0.025 kg and accelerates
at a rate of 5.0 m/s2. How much force is the wind exerting on the cup?
Givens
Solving For
Equation
Substitution
Answer with Units
4. You push a friend sitting on a swing. She has a mass of 50.0 kg and accelerates at a rate of 4.00 m/s2. Find
the force you exerted.
Givens
Solving For
Equation
Substitution
Answer with Units
5. How much force would it take to push another, larger friend who has a mass of 70.0 kg to accelerate at
the same rate of 4.00 m/s2?
Givens
Solving For
Equation
Substitution
Answer with Units
Name __________________
15
6. A worker drops his hammer off the roof of a house. The hammer has a mass of 9.0 kg, and gravity
accelerates it at the usual 9.8 m/s2. How much force does the earth apply to the hammer?
Givens
Solving For
Equation
Substitution
Answer with Units
7. You are a linebacker trying to sack the quarterback. You accelerate towards this hapless person at a rate
of 5.00 m/s2, and your mass is 100kg. Assuming that you sack him, with what force do you hit the
quarterback?
Givens
Solving For
Equation
Substitution
Answer with Units
8. An object with a mass of 2.0 kg has a force of 4.0 Newtons applied to it. What is the resulting
acceleration of the object?
Givens
Solving For
Equation
Substitution
Answer with Units
9. An object with a mass of 5.0 kg has a force of 20.0 Newtons applied to it. What is the resulting
acceleration of the object?
Givens
Solving For
Equation
Substitution
Answer with Units
10. An object accelerates 3.0 m/s2 when a force of 6.0 Newtons is applied to it. What is the mass of the
object?
Givens
Solving For
Equation
Substitution
Answer with Units
16
11. An object accelerates 12.0 m/s2 when a force of 6.0 Newtons is applied to it. What is the mass of the
object?
Givens
Solving For
Equation
Substitution
Answer with Units
12. An object accelerates 5.0 m/s2 when a force of 20.0 Newtons is applied to it. What is the mass of the
object?
Givens
Solving For
Equation
Substitution
Answer with Units
13. An object with a mass of 2.0 kg accelerates 2.0 m/s2 when an unknown force is applied to it. What is the
amount of the force?
Givens
Solving For
Equation
Substitution
Answer with Units
14. An object with a mass of 5.0 kg accelerates 8.0 m/s2 when an unknown force is applied to it. What is the
amount of the force?
Givens
Solving For
Equation
Substitution
Answer with Units
15. An object with a mass of 1.5 kg accelerates 10.0 m/s2 when an unknown force is applied to it. What is
the amount of the force?
Givens
Solving For
Equation
Substitution
Answer with Units
17
16. An object with a mass of 6.0 kg accelerates 4.0 m/s2 when an unknown force is applied to it. What is the
amount of the force?
Givens
Solving For
Equation
Substitution
Answer with Units
17. An object with a mass of 3.0 kg has a force of 9.0 Newtons applied to it. What is the resulting
acceleration of the object?
Givens
Solving For
Equation
Substitution
Answer with Units
18. An object with a mass of 3.2 kg has a force of 7.3 Newtons applied to it. What is the resulting
acceleration of the object?
Givens
Solving For
Equation
Substitution
Answer with Units
19. An object accelerates 8.2 m/s2 when a force of 20.1 Newtons is applied to it. What is the mass of the
object?
Givens
Solving For
Equation
Substitution
Answer with Units
20. An object with a mass of 6.3 kg has a force of 7.1 Newtons applied to it. What is the resulting
acceleration of the object?
Givens
Solving For
Equation
Substitution
Answer with Units
18
21. An object with a mass of 6.50 kg accelerates 12.3 m/s2 when an unknown force is applied to it. What is the
amount of the force?
Givens
Solving For
Equation
Substitution
Answer with Units
22. An object with a mass of 7.50 kg accelerates 8.30 m/s2 when an unknown force is applied to it. What is
the amount of the force?
Givens
Solving For
Equation
Substitution
Answer with Units
23. How much force is needed to accelerate a 66.0 kg skier at 2.00 m/sec2?
Givens
Solving For
Equation
Substitution
Answer with Units
24. What is the force on a 100.0 kg elevator that is falling freely at 9.8 m/sec2?
Givens
Solving For
Equation
Substitution
Answer with Units
25. What is the acceleration of a 50 kg object pushed with a force of 500.0 Newtons?
Givens
Solving For
Equation
Substitution
Answer with Units
26. A force of 250 N is applied to an object that accelerates at a rate of 5.0 m/s2. What is the mass of the
object?
Givens
Solving For
Equation
Substitution
Answer with Units
19
27. How much force is needed to accelerate a 44.0 kg skier at 3.00 m/sec2?
Givens
Solving For
Equation
Substitution
Answer with Units
28. What is the force on a 50.0 kg elevator that is falling freely at 9.80 m/sec2?
Givens
Solving For
Equation
Substitution
Answer with Units
29. What is the acceleration of a 40.0 kg object pushed with a force of 350.0 Newtons?
Givens
Solving For
Equation
Substitution
Answer with Units
30. The mass of a large car is 1001 kg. How much force would be required to accelerate the car at a rate of
3.000 m/s2?
Givens
Solving For
Equation
Substitution
Answer with Units
31. A 50.0 kg skater pushed by a friend accelerates 5.00 m/sec2. How much force did the friend apply?
Givens
Solving For
Equation
Substitution
Answer with Units
32. A force of 350 N is applied to an object that accelerates at a rate of 6.0 m/s2. What is the mass of the
object?
Givens
Solving For
Equation
Substitution
Answer with Units
20
33. A bowling ball rolled with a force of 15 N accelerates at a rate of 3.0 m/sec2; a second ball rolled with
the same force accelerates 4.0 m/sec2. What are the masses of the two balls?
Ball #1 Givens
Solving For
Equation
Substitution
Answer with Units
34. Ball #2
Ball #2 Givens
Solving For
Equation
Substitution
Answer with Units
35. If a 60 kg person on a 15 kg sled is pushed with a force of 300.0 N, what will be person’s acceleration?
You have to add the two kg together!!
Givens
Solving For
Equation
Substitution
Answer with Units
36. A force of 20.0 N acts upon a 5.0 kg block. Calculate the acceleration of the object.
Givens
Solving For
Equation
Substitution
Answer with Units
37. An object with a mass of 30.0 kg is observed to accelerate at the rate of 4.0 m/s2. Calculate the force
required to produce this acceleration.
Givens
Solving For
Equation
Substitution
Answer with Units
38. A 5.0 kg block is pulled across a table by a horizontal force of 40 N with a frictional force of 8 N
opposing the motion. Calculate the acceleration of the object. (Subtract the two N before you start)
Givens
Solving For
Equation
Substitution
Answer with Units
21
39. An object of mass 30.0 kg is in free fall in a vacuum where there is no air resistance. It is falling freely
at 9.8 m/sec2 Determine the amount of force that acted on the object.
Givens
Solving For
Equation
Substitution
Answer with Units
40. A man hits a baseball (0.60 kg) which accelerates at a rate of 35 m/s2. What amount of force acted on
the ball?
Givens
Solving For
Equation
Substitution
Answer with Units
41. You give a cart a shove down the hallway. The cart is full of textbooks and has a mass of 38.0 kg. The
cart accelerates at a rate of 5.0 m/s2. How much force did you exert on the cart?
Givens
Solving For
Equation
Substitution
Answer with Units
42. The wind pushes a paper cup along the sand at a beach. The cup has a mass of 0.035 kg and accelerates
at a rate of 6.0 m/s2. How much force is the wind exerting on the cup?
Givens
Solving For
Equation
Substitution
Answer with Units
43. You push a large friend sitting on a swing. He has a mass of 60.0 kg and accelerates at a rate of 4.0 m/s2.
Find the force you exerted.
Givens
Solving For
Equation
Substitution
Answer with Units
44. How much force would it take to push another, larger friend who has a mass of 80.0 kg to accelerate at
the same rate of 4.0 m/s2?
Givens
Solving For
Equation
Substitution
Answer with Units
22
45. A worker drops a pack of shingles off the roof of a house. The shingles have a mass of 89.0 kg, and
gravity accelerates it at the usual 9.80 m/s2. How much force does the earth apply to the pack of
shingles?
Givens
Solving For
Equation
Substitution
Answer with Units
46. Your bicycle has a mass of 9.1 kilograms. You accelerate at a rate of 1.79 m/s2 . Calculate the net force
that is accelerating the bicycle.
Givens
Solving For
Equation
Substitution
Answer with Units
47. The Space Shuttle has a liftoff mass of 2,062,500kg and accelerates at a rate of 16 m/s2. Calculate the
force (thrust) that is accelerating the Space Shuttle.
Givens
Solving For
Equation
Substitution
Answer with Units
48. A runner has a mass of 89 kilograms. He produces a force of 84 Newtons between the ground and his
running shoes. What is his acceleration?
Givens
Solving For
Equation
Substitution
Answer with Units
49. A rocket accelerates at 56.0 m/s2 with the force (thrust) of 44,900 N. What is the mass of the rocket?
Givens
Solving For
Equation
Substitution
Answer with Units
50. Calculate the acceleration of a car if the force on the car is 450 Newtons and the mass is 1300 kilograms.
Givens
Solving For
Equation
Substitution
Answer with Units
23
24
Name________________________ Answer Sheet for Calculating Force Worksheet Force Problems – choose the correct answer choice and mark it on your answer sheet. If you don’t see the
correct answer, rework it to make sure you did it right!
________1. a. 0.01 N b. 4 J c. 100 J d. 4 N
________2. a. 6N b. 5.4 J c. 54 N d. .167 N
________3. a. .005 N b. 200 N c. .125 N d. 20.0 J
________4. a. 0.08 N b. 20.0 J c. 200 N d. 12.5 N
________5. a. 17.5 N b. 280 N c. 28.0 J d. 0.06 N
________6. a. 88.2 J b. 88.2 m/s2 c. 88.2 N d. 1.09 N
________7. a. 20 N b. 500 J c. 500 N d. 0.05N
________8. a. 2 m/s2 b. 0.5 m/s2 c. 8 m/s2 d. 4 m/s2
________9. a. 4 m/s2 b. 100 m/s2 c. .25 m/s2 d. 4J
________10. a. 0.5 g b. 2 g c. 18 g d. 2 J
________11. a. 0.5 g b. 2 g c. 72 g d. 0.5 N
________12. a. 100 g b. 4 N c. 4 g d. 0.25 g
________13. a. 1N b. 4 J c. 4 N d. 1 J
________14. a. 1.6 N b. 0.625 N c. 40 N d. 40 J
________15. a. 15 N b. 15 J c. .15 N d. 6.67 N
________16. a. 0.67 N b. 24 N c. 1.5 N d. 24 J
________17. a. 0.33 m/s2 b. 3 N c. 3 m/s2 d. 27 m/s2
________18. a. 0.44 m/s2 b. 23.36 m/s2 c. 2.28 m/s2 d. 2.28 J
________19. a. 2.45 N b. 164.82 kg c. 0.41 kg d. 2.45 kg
________20. a. 44.73 m/s2 b. 1.13 m/s2 c. 0.87 m/s2 d. 1.13 N
________21. a. 32.595 J b. 325.95 N c. 1.9 N d. 0.53 N
________22. a. 62.25 N b. 0.90 N c. 1.1 N d. 622.5 J
________23. a. 13.2 J b. 33 N c. 132 N d. 0.03 N
________24. a. 98.00 J b. 102 N c. 0.0098 N d. 9800 N
________25. a. 0.1 m/s2 b. 25000 m/s2 c. 10 m/s2 d. 10 N
________26. a. 1250 kg b. 0.2 kg c. 12.50 kg d. 50 kg
25
________27. a. 14.7 b. 132 c. 0.68
________28. a. 490 b. 0.196 c. 5.00
________29. a. 14000 b. 8.75 c. 0.114
________30. a. 0.002997 b. 3003 c. 333.7
________31. a. 10.0 b. 250 c. 0.100
________32. a. 2100 b. 0.017 c. 58
________33. a. 0.20 b. 45 c. 5.0
________34. a. 3.8 b. 0.27 c. 60
________35. a. 0.25 b. 4.0 c. 2.3 x 104
________36. a. 0.25 b. 100 c. 4.0
________37. a. 120 b. 7.5 c. 0.13
________38. a. 160 b. 0.16 c. 6.4
________39. a. 0.327 b. 294 c. 3.06
________40. a. 58 b. 21 c. 0.017
________41. a. 7.6 b. 0.13 c. 190
________42. a. 0.21 b. 170 c. 0.0058
________43. a. 0.067 b. 15 c. 240
________44. a. 20 b. 0.050 c. 320
________45. a. 872 b. 9.08 c. 0.110
________46. a. 0.20 b. 5.1 c. 16
________47. a. 3.3 x 107 b. 1.3 x 105 c. 7.8 x 10-6
________48. a. 0.94 b. 1.1 c. 7476
________49. a. 802 b. 2.51 x 106 c. 0.00125
________50. a. 2.9 b. 0.35 c. 5.1 x 105
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Calculating Acceleration and Velocity Name _____________________
Change in Velocity = Final velocity - Starting Velocity
Change in VelocityAcceleration =
Time
For some of these questions, you have to determine the change in velocity first! Anything at a standstill or
complete stop is 0!!!
Sample Problem: A car starts from a stoplight and is traveling with a velocity of 10 m/sec east in 20 seconds. What is the acceleration of
the car?
First we identify the information that we are given in the problem:
vf - 10 m/sec
vi - 0 m/sec
time - 20 seconds
Then we insert the given information into the acceleration formula:
A = (vf - vi)/t
A = (10 m/sec - 0 m/sec)/20 sec A = 10 m/sec/ 20 sec
A = 0.5 m/s2
Answer the following problems. Write down your equation, substitute in your equation and solve your equation.
YES! I added in a step from yesterday!
1. A car goes from 0 to 100 m/s in 10 seconds. What is its acceleration? Givens
From 0 m/s to 100 m/s 10. sec Solving For
acceleration
Equation
A = ∆ V (vf - vi)
T
Substitution
A = (100-0)
10
Answer with Units
10 m/s2
2. A bus slams on its breaks and goes from 30.0 m/s to 15.0 m/s in 4.00 seconds. What is its acceleration? Givens
Solving For
Equation
Substitution
Answer with Units
3. A roller coaster’s velocity at the top of a hill is 10.0 m/s. 2.0 seconds later it reaches the bottom of the hill
with a velocity of 26.0 m/s. What was the acceleration of the coaster? Givens
Solving For
Equation
Substitution
Answer with Units
Time = ∆ V (vf - vi)
acceleration ∆ V (vf - vi)= acceleration * Time
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4. A roller coaster is moving at 25 m/s at the bottom of a hill. 3.0 seconds later it reaches the top of the
hill moving at 10 m/s. What was the acceleration of the coaster? Givens
Solving For
Equation
Substitution
Answer with Units
5. If a Ferrari, with an initial velocity of 10.0 m/s, accelerates at a rate of 50.0 m/s2 for 3.00 seconds, what will
its final velocity be? Givens
Solving For
Equation
vf = (A * T) + vi
Substitution
Answer with Units
6. A rabbit changes speed as a dog chases it. The rabbit travels at a speed from 1.2 m/s to 3.4 m/s in a time of
5.0 seconds, what is the rabbit’s acceleration? Givens
Solving For
Equation
Substitution
Answer with Units
7. A rock accelerates toward the ground at 9.8 m/s2 when dropped from the top of a bridge. If the rock is
originally at rest (initial velocity = 0 m/s), and falls for 4.78 s, how fast is it going just before it hits the
ground? This is the final velocity. Givens
Solving For
Equation
Substitution
Answer with Units
8. A car traveling initially at 7.0 m/s speeds up to a velocity of 12.0 m/s in 2.0 seconds. What was the
average acceleration? Givens
Solving For
Equation
Substitution
Answer with Units
30
9. Turner’s treadmill starts with a velocity of 6.5 m/s and speeds up to 1.2 m/s in 25 minutes (1500 seconds –
you have to use the seconds to do the math). What is the average acceleration of the treadmill? Givens
Solving For
Equation
Substitution
Answer with Units
10. What is the acceleration of a sprinter if he increases his speed from 0 m/s to 12 m/s in 0.50 seconds? Givens
Solving For
Equation
Substitution
Answer with Units
11. A car moves from a standstill (0 m/s) to 60 m/s in 10 seconds. What is the acceleration? Givens
Solving For
Equation
Substitution
Answer with Units
12. A train is accelerating at a rate of 2.0 m/s2. If its initial velocity is 20.0 m/s, what is its velocity after 30.0
seconds? Givens
Solving For
Equation
Substitution
Answer with Units
13. A runner achieves a velocity of 11.1 m/s, 9.0 sec after he begins (0 m/s). What is his acceleration? Givens
Solving For
Equation
Substitution
Answer with Units
14. In 0.50 seconds, a projectile goes from 0 to 300 m/s. What is the acceleration of the projectile? Givens
Solving For
Equation
Substitution
Answer with Units
31
15. A meteoroid changed velocity from 1.0 km/s to 1.8 km/s in 0.030 seconds. What is the acceleration of the
meteoroid? Givens
Solving For
Equation
Substitution
Answer with Units
16. The space shuttle releases a space telescope into orbit around the earth. The telescope goes from being
stationary to traveling at a speed of 1700 m/s in 25 seconds. What is the acceleration of the satellite? Givens
Solving For
Equation
Substitution
Answer with Units
17. A lizard runs from 2.0 m/s to 10.0 m/s in 4.0 seconds. What is the lizard’s average acceleration? Givens
Solving For
Equation
Substitution
Answer with Units
18. If a Ferrari, with an initial velocity of 10 m/s and a final velocity of 160 m/s and it accelerates at a rate of
50 m/s2 , how many seconds does it take for it to achieve its final velocity? Givens
Solving For
Equation
Substitution
Answer with Units
19. A turtle has a speed of 0.50 m/s. After 6.0 seconds, it has a speed of 0.80 m/s. What is his acceleration? Givens
Solving For
Equation
Substitution
Answer with Units
20. What is a sport’s car average acceleration if it can go from 0 m/s to 27 m/s in 6.0 sec? Givens
Solving For
Equation
Substitution
Answer with Units
32
21. A school bus’s acceleration from a complete stop (0 m/s) is 1.3 m/s2. How long will it take the bus to reach a
speed of 12.1 m/s? (Hint: Think about this….you are looking for a time and the initial velocity is 0 m/s) Givens
Solving For
Equation
T = ∆ V (vf - vi)
A
Substitution
Answer with Units
22. If a bicycle has an average acceleration of 0.44 m/s2, and its initial forward velocity is 8.20 m/s, what is its
final velocity after 10.0 seconds? Givens
Solving For
Equation
Substitution
Answer with Units
23. What is a car’s acceleration when there is an accident on the highway the car slows down from an initial
velocity of 24.5 m/s to a final velocity of 4.5 m/s in 3.2 seconds?
Givens
Solving For
Equation
Substitution
Answer with Units
24. With an average acceleration of -0.50 m/s2, how long will it take a cyclist to bring a bicycle with an initial
velocity +13.5 m/s to a complete stop. Givens
Solving For
Equation
Substitution
Answer with Units
25. The final velocity of a car is 30 m/s. The car is accelerating at a rate of 2.5 m/s2 over an 8.0 second period
of time. What is the initial velocity of the car?
Givens
Solving For
Equation
Substitution
Answer with Units
33
26. A skier accelerates at a rate of 4.6 m/s2 for 4.5s. What is his initial velocity if his final velocity is 21 m/s? Givens
Solving For
Equation
Substitution
Answer with Units
27. A car accelerates at a rate of 3.0 m/s2. If its original velocity is 8.0 m/s, how many seconds will it take the
car to reach a final velocity of 25.0 m/s?
Givens
Solving For
Equation
Substitution
Answer with Units
28. A cyclist accelerates at a rate of 7.0 m/s2. How long will it take the cyclist to reach a speed of 18 m/s.
Remember…he started a 0 m/s Givens
Solving For
Equation
Substitution
Answer with Units
29. A train is moving slowly through a city. Once outside the city, the engine accelerates at 0.40 m/s2 for
60.0 sec. After this acceleration, the velocity of the train is 30.0 m/s. What is the initial velocity?
Givens
Solving For
Equation
Substitution
Answer with Units
30. If a cyclist had an average acceleration of 4.0 m/s and after 10.0 sec, his final velocity was 60.0 m/s, what
was his initial velocity?
Givens
Solving For
Equation
Substitution
Answer with Units
34
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Name _____________________________
Answer sheet for Acceleration, Velocity and Time Worksheet
Choose the correct answer choice and mark it on your answer sheet. IF you don’t see the correct
answer, rework it to make sure you did it right!
________1. A. 1000 B. 0.10 C. 10
________2. A. -3.75 B. 3.75 C. 1.73
________3. A. 2.4 B. 8.0 C. -8.0
________4. A. 5.0 B. 7.3 C. -5.0
________5. A. 80 B. 503 C. 160
________6. A. 0.44 B. -0.44 C. 1.3
________7. A. 47 B. 0 C. 2.1
________8. A. -2.5 B. 5.0 C. 2.5
________9. A. 0.0035 B. -0.0035 C. 283
________10. A. 24 B. -24 C. 0.042
________11. A. -6.0 B. 0.17 C. 6.0
________12. A. 70 B. 80 C. 602
________13. A. -1.2 B. 0.81 C. 1.2
________14. A. 600 B. -600 C. 0.0017
________15. A. 1.8 B. -27 C. 27
________16. A. 68 B. -68 C. 0.015
________17. A. -2.0 B. 3.0 C. 2.0
________18. A. -3.0 B. 3.0 C. 11
________19. A. 6.9 B. 0.5 C. -0.5
________20. A. -4.5 B. 0.22 C. 4.5
________21. A. 9.3 B. 0.11 C. -9.3
________22. A. 12.6 B. 82.4 C. 13.6
________23. A. -6.3 B. 0.053 C. 4.7
________24. A. 27 B. -27 C. 0.037
________25. A. 50 B. 60 C. 10
________26. A. 41.7 B. 0.3 C. -0.3
________27. A. 5.7 B. 2.8 C. 0.20
________28. A. 0 B. 0.39 C. 2.6
________29. A. 1776 B. 12 C. 6
________30. A. 2000 B. 200 C. 20
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Name___________________________________
Practice Worksheet: Net Force and Acceleration
For each of the following problems, give the net force on the block, and the acceleration, including units.
1) 2)
Net Force = ________ a = F/m = _______ Net Force = ________ a = F/m = _______
3) 4)
Net Force = ________ a = _______ Net Force = ________
a = __________
5)
Net Force = ________ a = _______
For problems 6-9, using the formula net Force = Mass • Acceleration, calculate the net force on the
object.
6) 7)
F = m•a = _____________ F = m•a = _____________
8) 9)
F = m•a = _____________ F = m•a = _____________
26 N 12 N 7 kg
180 N
20 N
40 kg 70 N
190 N
20 kg
200 N 30 N 100 kg
60 N
300 N
40 kg
9 kg a = 3 m/s2
5 kg a = 40 m/s2
12 kg a = 4 m/s2
200 kg a = 6 m/s2
39
Net Force Worksheet
The force that results from all the combined forces acting on the object is called the net force. Calculate the net force acting on the box in the following problems. Be sure to include the direction of the net force (left or right)!
1.
4 N
2.
7N 2 N
Net Force Net Force: 5 N to the left Because 7-2 is 5 and it would move left
3.
4N
4N
4.
6N 3N
Net Force Net Force
5.
8N 4N
6.
4N 5N
Net Force Net Force
7.
3N 3N
8.
2N
4N 5N
Net Force Net Force
9.
6N 3N
10.
7N
4N 4N
Net Force Net Force
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Name: Period: Date:
CALCULATING WEIGHT WORKSHEET (Newton’s 2nd Law)
Strength of gravity (g) on the surface, in Newtons per Kilogram (N/kg)
Mercury
Venus
Moon
Mars
Jupiter
Saturn
Uranus
Neptune
Pluto
3.8 8.8 1.6 3.7 23.1 9.0 8.7 11.0 0.6
Use the formula weight = mass x g to answer the questions below.
Calculate weight (force due to gravity) in the following problems by using the equation:
weight = mass x free-fall acceleration w = m * g
g (on Earth) = 9.81 m/s2
1. A physical science text book has a mass of 2.2 kg What is the weight on the Earth?
Givens
Solving For
Equation
Substitution
Answer with Units
2. What is the weight of the textbook in question #1 on Mars (g = 3.7 m/s2)
Givens
Solving For
Equation
Substitution
Answer with Units
3. If the textbook in #1 weighs 19.6 newtons on Venus, what is the strength of gravity on Venus?
Givens
Solving For
Equation
Substitution
Answer with Units
4. Of all the planets in our solar system, Jupiter has the greatest gravitational strength. If a 0.5 kg
pair of running shoes would weigh 11.55 newtons on Jupiter, what is the strength of gravity there?
Givens
Solving For
Equation
Substitution
Answer with Units
41
Name: Period: Date:
5. If the pair of shoes in #4 weighs 0.3 newtons on Pluto, what is the strength of gravity on Pluto?
Givens
Solving For
Equation
Substitution
Answer with Units
6. What does the pair of shoes in #4 weigh on Earth?
Givens
Solving For
Equation
Substitution
Answer with Units
7. How much would a 25 kg suitcase weigh on the surface of Mercury?
Givens
Solving For
Equation
Substitution
Answer with Units
8. How much would a 25 kg suitcase weigh on the surface of Venus?
Givens
Solving For
Equation
Substitution
Answer with Units
9. How much would a 25 kg suitcase weigh on the surface of Jupiter?
Givens
Solving For
Equation
Substitution
Answer with Units
10. How much would a 25 kg suitcase weigh on the surface of Uranus?
Givens
Solving For
Equation
Substitution
Answer with Units
42
Name: Period: Date:
11.. How much would a10 kg suitcase weigh on the surface of The Moon?
Givens
Solving For
Equation
Substitution
Answer with Units
12.. How much would a10 kg suitcase weigh on the surface of Mars?
Givens
Solving For
Equation
Substitution
Answer with Units
13.. How much would a10 kg suitcase weigh on the surface of Saturn?
Givens
Solving For
Equation
Substitution
Answer with Units
14. How much would a10 kg suitcase weigh on the surface of Pluto?
Givens
Solving For
Equation
Substitution
Answer with Units
15. What would be the weight of a 10 kg suitcase be on Mercury?
Givens
Solving For
Equation
Substitution
Answer with Units
16. What would be the weight of a 10 kg suitcase be on Venus?
Givens
Solving For
Equation
Substitution
Answer with Units
43
Name: Period: Date:
Calculating Weight Answer sheet - choose the correct answer choice and mark it on your
answer sheet. If you don’t see the correct answer, rework it to make sure you did it right!
____1. a. 0.22 N b. 4.46 N c. 21.582 N
____2. a. 0.59 N b. 8.14 N c. 1.68 N
____3. a. 8.9 m/s2 b. 43.12 m/s2 c. 0.11 m/s2
____4. a. 23.1 m/s2 b. 0.04 m/s2 c. 5.775 m/s2
____5. a. 1.67 m/s2 b. 0.15 m/s2 c. 0.6 m/s2
____6. a. 19.62 N b. 0.05 N c. 4.905 N
____7. a. 95 N b. 6.58 N c. 0.152 N
____8. a. 2.84 N b. 0.352 N c. 220 N
____9. a. 1.08 N b. 577.5 N c. 0.924 N
____10. a. 0.35 N b. 217.5 N c. 3.22 N
____11. a. 0.16 N b. 16 N c. 6.25 N
____12. a. 37 N b. 0.27 N c. 3.7 N
____13. a. 1.1 N b. 9 N c. 90 N
____14. a. 0.06 N b. 6 N c. 16.67 N
____15. a. 0.38 N b. 2.63 N c. 38 N
____16. a. 88 N b. 0.88 N c. 1.14 N
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Name:____________________________________Block: :___ Date:_______________ MS- Momentum Practice Problems Which is more difficult to stop: A tractor-trailer truck barreling down the highway at 35 meters per second, or a small two-seater sports car traveling the same speed? You probably guessed that it takes more force to stop a large truck than a small car. In physics terms, we say that the truck has greater momentum. We can find momentum using this equation:
momentum = mass of object × velocity of object Velocity is a term that refers to both speed and direction. For our purposes we will assume that the vehicles are traveling in a straight line. In that case, velocity and speed are the same. The equation for momentum is abbreviated like this: p=m×v Momentum, symbolized with a p, is expressed in units of kg·m/sec; m is the mass of the object, in kilograms; and v is the velocity of the object in m/sec. Make sure to use the correct unit in your final answer in all of your answers. Use your knowledge about solving equations to work out the following problems. Be sure to show all your work with units:
1. If the truck has a mass of 2,000 kilograms, what is its momentum? (v = 35 m/s)
Equation Substitution Answer with Units
2. If the car has a mass of 1,000 kilograms, what is its momentum? (v = 35 m/s)
Equation Substitution Answer with Units
3. An 8-kilogram bowling ball is rolling in a straight line toward you. If its momentum is
16 kg·m/sec, what is its velocity?
Equation Substitution Answer with Units
4. A beach ball is rolling in a straight line toward you at a speed of 0.5 m/sec. Its momentum
is 0.25 kg·m/sec. What is the mass of the beach ball?
Equation Substitution Answer with Units
47
5. A 4,000-kilogram truck travels in a straight line at 10.0 m/sec. What is its momentum?
Equation Substitution Answer with Units
6. A 1,400-kilogram car is also traveling in a straight line. Its momentum is equal to that of
the truck in the previous question (the answer). What is the velocity of the car? You use the momentum you calculated in Question #5.
Equation Substitution Answer with Units
7. How much momentum would it take to stop a 4.0-kilogram ball rolling along the path at a
speed of 1.0 m/sec?
Equation Substitution Answer with Units
8. How much momentum would it take to stop an 8.0-kilogram ball rolling in a straight line at
a speed of 0.2 m/sec?
Equation Substitution Answer with Units
9. The momentum of a car traveling in a straight line at 20 m/sec is 24,500 kg·m/sec. What
is the car’s mass?
Equation Substitution Answer with Units
10. A 0.14-kilogram baseball is thrown in a straight line at a velocity of 30 m/sec. What is the
momentum of the baseball?
Equation Substitution Answer with Units
11. Another pitcher throws the same baseball (0.14 kg) in a straight line. Its momentum is 2.1
kg·m/sec. What is the velocity of the ball?
Equation Substitution Answer with Units
48
12. A 3-kg turtle crawls in a straight line at a speed of 0.02 m/sec. What is the turtle’s momentum?
Equation Substitution Answer with Units
13. What is the momentum of a 0.25 kg bug flying with a speed of 12 m/s?
Equation Substitution Answer with Units
14. What is the momentum of a 112 kg quarterback running with a speed of 4.8 m/s?
Equation Substitution Answer with Units
15. A steel ball whose mass is 2.0 kg is rolling at a rate of 2.8 m/s. What is its momentum?
Equation Substitution Answer with Units
16. A marble is rolling at a velocity of 1.5 m/s with a momentum of 0.10 kg·m/s. What is its
mass? You will have to keep three after the decimal on this question
Equation Substitution Answer with Units
17. On April 15, 1912, the luxury cruise liner Titanic sank after running into an iceberg. What
was the cruise liner’s speed (velocity) when it collided with the ice berg if it had a mass of 4.23 x 108 kg ship and a momentum of 4.9 x 109 kg·m/s? (You just put the scientific notation in the calculator and let it calculate your answer)
Equation Substitution Answer with Units
18. How much momentum does a 988 kg car moving 3 m/s have?
Equation Substitution Answer with Units
49
19. How much momentum does a 70 kg person sprinting at 8 m/s have?
Equation Substitution Answer with Units
20. What is the velocity of a 5.5 kg object that has a momentum of 550 kg·m/s?
Equation Substitution Answer with Units
21. What is Object A’s momentum if m = 2 kg, v = 125 m/s
Equation Substitution Answer with Units
22. What is Object B’s momentum if: m = 10 kg, v = 12 m/s
Equation Substitution Answer with Units
23. What is Object C’s momentum if: m = 0.5 kg, v = 985 m/s
Equation Substitution Answer with Units
24. What is Object D’s momentum if: m = 100 kg, v = 2 m/s
Equation Substitution Answer with Units
25. How much momentum does a 22 kg mass moving at 23 m/s have?
Equation Substitution Answer with Units
26. Calculate the momentum of a 1200kg car with a velocity of 25m/s.
Equation Substitution Answer with Units
50
27. Calculate the momentum of a 50 kg dolphin swimming at 16.4 m/s
Equation Substitution Answer with Units
28. Calculate the momentum of a 4100 kg elephant walking 0.20 m/s.
Equation Substitution Answer with Units
29. What is the momentum of a child and wagon if the total mass of the child and wagon is 22kg and the velocity is 1.5m/s?
Equation Substitution Answer with Units
30. The parking brake on a 1200kg automobile has broken, and the vehicle has reached a
momentum of 7800kg•m/s. What is the velocity of the vehicle?
Equation Substitution Answer with Units
31. A toy dart gun generates a dart with 140kg.m/s momentum and a velocity of 4m/s. What
is the mass of the dart?
Equation Substitution Answer with Units
32. A bowling ball of 35.2kg, generates 218 kg•m/s units of momentum. What is the velocity
of the bowling ball?
Equation Substitution Answer with Units
33. A school bus traveling at 11.1m/s has a momentum of 152625 kg•m/s. What is the mass
of the bus?
Equation Substitution Answer with Units
51
34. A deer with a mass of 146 kg is running head on toward you with a speed of 17 m/s. Find the momentum of the deer.
Equation Substitution Answer with Units
35. Calculate the momentum of a 1.60 x 103 kg car traveling at 20.0 m/s.
Equation Substitution Answer with Units
36. How fast is a 1.50 kg ball moving if it has a momentum of 4.50 kg.m/s?
Equation Substitution Answer with Units
37. A 75.0 g ball is rolling at a speed of 57.0 m/s. Calculate the ball’s momentum
Equation Substitution Answer with Units
38. A supersonic bomber, with a mass of 21,000 kg, departs from its home airbase with a
velocity of 400 m/s due east. What is the jet's momentum?
Equation Substitution Answer with Units
39. Now, let's assume the jet drops its payload and has burned up most of its fuel as it
continues its journey to its destination air field. If the jet's new mass is 16,000 kg, and due to its reduced weight the pilot increases the cruising speed to 550 m/s, what is the jet's new momentum?
Equation Substitution Answer with Units
40. A 60 kg halfback is moving at 9 m/s. What is their momentum?
Equation Substitution Answer with Units
52
41. What is the momentum of a 1,000 kg car moving at 20 m/s.
Equation Substitution Answer with Units
42. Calculate the momentum of an athlete with a mass of 60kg running at a velocity of 10 m/s
Equation Substitution Answer with Units
43. Calculate the momentum of a car with a mass of 800 kg traveling at a velocity of 5 m/s
Equation Substitution Answer with Units
44. Calculate the momentum of a ship that has a mass of 20,000,000 kg traveling at a
velocity of 5 m/s
Equation Substitution Answer with Units
45. What is the momentum of a plane whose mass is 80,000 kg traveling at a velocity of 300 m/s.
Equation Substitution Answer with Units
46. Calculate the momentum of a rocket who has a mas of 100,000 kg traveling at a velocity
of 2,000 m/s
Equation Substitution Answer with Units
47. Calculate the momentum of a football who has a mass of .5 kg traveling at a velocity of
10 m/s
Equation Substitution Answer with Units
53
48. An athlete running at 8 m/s has a momentum of 520 kg • m/s, what is her mass?
Equation Substitution Answer with Units
49. A toy train of a mass of 2.0 kg is moving right at 1.8 m/s. What is its momentum?
Equation Substitution Answer with Units
50. A dump truck has a momentum of 360,000 kg • m/s and a velocity of 15 m/s. What is the mass of the truck?
Equation Substitution Answer with Units
51. A bullet has a momentum of 12 kg • m/s and a mass of 0.050 kg. What is its velocity?
Equation Substitution Answer with Units
52. What is the mass of a quarterback running with a speed of 4.8 m/s and a momentum of
5.4 x 102 kg • m/s?
Equation Substitution Answer with Units
53. If you have a car moving at a velocity of 28.6 m/s and has a momentum of 40,000 kg•m/s, what is its mass?
Equation Substitution Answer with Units
54. If you have a car with a mass of 1,225 kg moving at a momentum of 24,500 kg•m/s, what is its velocity?
Equation Substitution Answer with Units
54
Name _______________________________ Answer Sheet for Momentum
____1. A. 57.14 B. 70,000 C. 0.175 ____2. A. 35,000 B. 28.57 C. 0.35 ____3. A. 128 B. 0.5 C. 2 ____4. A. 0.5 B. 0.125 C. 2 ____5. A. .0025 B. 400 C. 40,000 ____6. A. 28.6 B. 0.286 C. 3.5 ____7. A. 1.6 B. 0.25 C. 4 ____8. A. 4 B. 1.6 C. 40 ____9. A. 1225 B. 490000 C. 8.2 x 10-4 ____10. A. 4.2 B. 0.00467 C. 2.1 ____11. A. 0.067 B. 15 C. 0.294 ____12. A. 0.67 B. 0.06 C. 150 ____13. A. 3 B. 48 C. 0.0208 ____14. A. .043 B. 537.6 C. 23.3 ____15. A. 1.4 B. 5.6 C. 1.4 ____16. A. 0.667 B. 15 C. 0.15 ____17. A. 0.086 B. 2.07x1018 C. 0.11.6 ____18. A. 0.003 B. 329.67 C. 2964 ____19. A. 8.75 B. 560 C. 0.114 ____20. A. 0.1 B. 100 C. 3023 ____21. A. 250 B. 0.016 C. 62.5 ____22. A. 0.83 B. 1.2 C. 120 ____23. A. 1970 B. 492.5 C. 5.08x10-4 ____24. A. 0.2 B. 50 C. 200 ____25. A. 506 B. 1.05 C. 0.96 ____26. A. 0.02 B. 48 C. 30,000 ____27. A. 3.28 B. 820 C. 0.305 ____28. A. 20,500 B. 820 C. 4.88x10-5 ____29. A. 33 B. 14.67 C. 0.068 ____30. A. 0.154 B. 9360000 C. 6.5 ____31. A. 560 B. 35 C. 0.029 ____32. A. 7673.6 B. 0.16 C. 6.2 ____33. A. 13,750 B. 7.27x10-5 C. 1694137.5 ____34. A. 0.116 B. 2482 C. 8.59 ____35. A. 0.0125 B. 80 C. 32,000 ____36. A. 3 B. 6.75 C. 0.33 ____37. A. 1.32 B. 4275 C. 0.76 ____38. A. 52.5 B. 0.019 C. 8,400,000 ____39. A. 8,800,000 B. 29.09 C. 0.034 ____40. A. 0.15 B. 6.67 C. 540 ____41. A. 50 B. 0.02 C. 20,000 ____42. A. 600 B. 6 C. 0.167 ____43. A. 4,000 B. 160 C. 0.00625 ____44. A. 1000 B. 100,000,000 C. 4,000,000 ____45. A. 24,000,000 B. 266.67 C. 0.00375 ____46. A. 33.33 B. 200,000,000 C. 6.03 ____47. A. 5 B. 20 C. 0.05 ____48. A. 0.015 B. 4,160 C. 65 ____49. A. 0.9 B. 3.6 C. 1.1 ____50. A. 24,000 B. 5,400,000 C. 4.167x10-5 ____51. A. 0.004167 B0.6 C. 240 ____52. A. 112.5 B. 2592 C. 0.0089 ____53. A. 7.15x10-4 B. 1,144,000 C. 1,398.6
____54. A. 20 B. 0.05 C. 30,012,500
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Name Quiz
Class
Student ID
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
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3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
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3
4
5
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9
0
1
2
3
4
5
6
7
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9
Mom
entu
m P
ract
ice
Prob
lem
s (6
409)
Zip
Grade.c
om
1 A B C
2 A B C
3 A B C
4 A B C
5 A B C
6 A B C
7 A B C
8 A B C
9 A B C
10 A B C
11 A B C
12 A B C
13 A B C
14 A B C
15 A B C
16 A B C
17 A B C
18 A B C
19 A B C
20 A B C
21 A B C
22 A B C
23 A B C
24 A B C
25 A B C
26 A B C
27 A B C
28 A B C
29 A B C
30 A B C
31 A B C
32 A B C
33 A B C
34 A B C
35 A B C
36 A B C
37 A B C
38 A B C
39 A B C
40 A B C
41 A B C
42 A B C
43 A B C
44 A B C
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46 A B C
47 A B C
48 A B C
49 A B C
50 A B C
51 A B C
52 A B C
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Test #
Typ
e (P
refix, Ro
ot o
r
Suffix)
Ro
ot o
r Affix
M
ean
ing
Ex
am
ple
13
prefix
macro
large
m
acroeco
no
mics, m
acrosco
pic
13
prefix
mal
bad
m
alpractice
13
roo
t m
en
d
pu
t in th
e han
ds o
f, entru
st, ord
er co
mm
end
, recom
men
d
13
roo
t m
ania
o
bsessio
n
man
iac, beatlem
ania
13
roo
t m
anu
h
and
m
anu
al, man
ufactu
re
13
roo
t m
ar sea
m
arine
13
roo
t m
edio
, med
i m
idd
le
med
ian, med
iocrity
13
prefix
mega
large, great
megalo
po
lis, megalith
13
roo
t m
erc trad
e
com
merce, m
ercantile, m
erchan
t
13
roo
t m
etro
city state
metro
po
litan
13
prefix
micro
very sm
all m
icrob
e, micro
scop
e
13
roo
t m
igr/migrat
wan
der, m
ovin
g
migrate, m
igration
13
roo
t m
im
imitate
m
ime, m
imic, m
imeo
graph
13
roo
t minut,
small, little
m
inu
te
13
roo
t mit,
send
, miss
transm
it, remit, m
ission
13
prefix
mo
no
sin
gle, on
e
mo
no
theism
, mo
no
po
ly, mo
no
meter,
13
roo
t m
orp
ho
, mo
rph
sh
ape, fo
rm, ap
pearan
ce
mo
rph
ed
13
roo
t m
ort
death
m
ortician
, mo
rbid
13
prefix
mu
lti/mu
lt m
any, m
uch
m
ultip
ly
13
roo
t m
un
, mu
ner
shu
t, wall in, p
rotect, d
uty, service, gift
mu
nicip
al, remu
nerate, am
mu
nitio
n
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Nam
e ______
______
_____
______
______
_____
_______
Date __
____
____
______
____ B
lock __
____
__ Test # ____
____
(Fill this in
!!)
Ty
pe (P
refix, R
oo
t
or S
uffix
) ro
ot o
r affix
m
ean
ing
exa
mp
les
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62
Name _________________________________________Date ________________ Block Motions and Forces Review Sheet for test - Fill in the following chart
Speed, Time and Distance
10. Mike rides his bike with a constant speed of 14 miles per hour. How long will he take to travel a distance of 21
miles?
Givens Solving For
Equation Substitution Answer with Units
Formula Definition
1. Acceleration
2. Mass
3. Force
4. Velocity
5. Momentum
6. acceleration
7. Time
8. Speed
9. Distance
63
11. Nancy roller skates 18 km for 1.5 hours. How fast is she skating?
Givens Solving For
Equation Substitution Answer with Units
12. A van moves with a constant speed of 60 miles per hour. How far can it travel in 1.5 hours?
Givens Solving For
Equation Substitution Answer with Units
13. Noah rides his bike with a constant speed of 14 miles per hour. How far can he travel in 0.5 hours
Givens Solving For
Equation Substitution Answer with Units
14. A car drives with a constant speed of 32 km/h. How long will it take to travel a distance of 96 kilometers?
Givens Solving For
Equation Substitution Answer with Units
15. A minibus drives with a constant speed of 32 miles per hour. How far can it travel in 3 hours?
Givens Solving For
Equation Substitution Answer with Units
Time, Acceleration, Velocity
16. A car advertisement states that a certain car can travel from rest (0 km/hr) to 70 km/hr in 7 seconds. Find the car’s average acceleration.
Givens Solving For
Equation Substitution Answer with Units
64
17. A lizard travels from 2 m/s to 10 m/s in 4 seconds. What is the lizard’s average acceleration?
Givens Solving For
Equation Substitution Answer with Units
18. If a Ferrari, with an initial velocity of 10 m/s, accelerates at a rate of 50 m/s2 for 3 seconds, what will its final
velocity be?
Givens Solving For
Equation Substitution Answer with Units
19. While traveling along a highway a driver slows from 24 m/s to 15 m/s in 12 seconds. What is the automobile’s
acceleration? (Remember that a negative value indicates a slowing down or deceleration.)
Givens Solving For
Equation Substitution Answer with Units
20. A cyclist accelerates at a rate of 7.0 m/s2. How long will it take the cyclist to reach a speed of 18 m/s?
Givens Solving For
Equation Substitution Answer with Units
Force, Mass, Acceleration
21. A man hits a golf ball (0.2 kg) which accelerates at a rate of 20 m/s2. What amount of force acted on the ball?
Givens Solving For
Equation Substitution Answer with Units
65
22. You give a shopping cart a shove down the isle. The cart is full of groceries and has a mass of 18kg. The cart
accelerates at a rate of 3 m/s2. How much force did you exert on the cart?
Givens Solving For
Equation Substitution Answer with Units
23. The wind pushes a paper cup along the sand at a beach. The cup has a mass of 0.025 kg and accelerates at a rate
of 5 m/s2. How much force is the wind exerting on the cup?
Givens Solving For
Equation Substitution Answer with Units
24. An unbalanced 16 N force is applied to a 2.0 kg mass. What is the acceleration of the mass?
Givens Solving For
Equation Substitution Answer with Units
25. A shot-putter exerts an unbalanced force of 140 N on a shot giving it an acceleration of 19 m/s2. What is the
mass of the shot?
Givens Solving For
Equation Substitution Answer with Units
26. An object moving with a constant velocity has an unbalanced force applied to it. If the unbalanced force is
20.0 N and the mass of the object is 3.75 kg, what is the acceleration of the object while this force is acting?
Givens Solving For
Equation Substitution Answer with Units
66
27. A racing car undergoes a uniform acceleration of 8.00 m/s2. If the unbalanced force causing the acceleration is
6,000 N, what is the mass of the racing car?
Givens Solving For
Equation Substitution Answer with Units
28. How much force is needed to keep a 20 N stone from falling? Your acceleration is gravity – 9.81 m/s2
Givens Solving For
Equation Substitution Answer with Units
Momentum, velocity, Mass
29. What is the momentum of a 70 kg runner traveling at 10 m/s?
Givens Solving For
Equation Substitution Answer with Units
30. What is the momentum of a 47 gram tennis ball that is traveling at 40 m/s?
Givens Solving For
Equation Substitution Answer with Units
31. Calculate the momentum of a football who has a mass of .5 kg traveling at a velocity of 10 m/s
Givens Solving For
Equation Substitution Answer with Units
32. How fast is a 1.50 kg ball moving if it has a momentum of 4.50 kg.m/s?
Givens Solving For
Equation Substitution Answer with Units
67
33. Calculate the momentum of a rocket who has a mas of 100,000 kg traveling at a velocity of 2,000 m/s
Givens Solving For
Equation Substitution Answer with Units
34. A toy dart gun generates a dart with 140kg.m/s momentum and a velocity of 4m/s. What is the mass of the
dart?
Givens Solving For
Equation Substitution Answer with Units
Gravity, Mass and Weight Problems
35. The strength of gravity at the Earth's surface is 10 N. Calculate the weight of a car with a mass of 1500 kg.
Givens Solving For
Equation Substitution Answer with Units
36. The strength of gravity on the Moon is 1.6 N. If an astronaut's mass is 80 kg, what is his weight on the Moon?
Givens Solving For
Equation Substitution Answer with Units
37. The surface gravity of Jupiter is about 26 N. What would be the weight of a probe of mass 50 kg at Jupiter's
surface?
Givens Solving For
Equation Substitution Answer with Units
68
38. What is the mass of a person who weighs 500 N? Assuming 9.81 is Earth’s Gravity
Givens Solving For
Equation Substitution Answer with Units
39. A space ship has a mass of 9000 kg. The space ship is launched from Earth and lands on a
distant planet where it has a weight of 390000 N. What is the gravity on this planet?
Givens Solving For
Equation Substitution Answer with Units
Give the net force on the blocks and calculate the acceleration
69
70
Work, Power and Machines Work and Power
• Objectives: • 1. Describe the conditions that must exist for a force to do work on an object • 2. Calculate the work done on an object • 3. Describe and calculate power • 4. Compare units of watts and horsepower as they relate to power
Work and Power
• Work – done when a force acts on an object in the direction the object moves
– Requires Motion • Man is not actually doing work when holding barbell
above his head • Force is applied to barbell • If no movement, no work done
Work and Power Work Depends on Direction • All of the force does work on the suitcase.
• The horizontal part of the force does work. • The force does no work on the suitcase.
Conditions for Work
• Def: work is the product of force times distance • For a force to do work on an object, some of the force must act in the same
direction as the object moves • If the object does not move, no work is done • Work depends on direction • Any part of a force that does not act in the direction of motion does no work on the
object Calculating Work
• Work = Force x Distance • The units for force are Newtons, N • Recall from chapter 12 that 1 N = 1 kg*m/s2
• The unit for distance is the meter, m • The unit for force is 1 N*m or 1 kg*m2/s2 which equals one joule, abbreviated J • Work = Force x Distance
– W = Fd • Force = mass x acceleration → F = ma or F = mg
– Joule (J) = SI unit for work • Unit: J = N(m) • Named after James Prescott Joule (1818 – 1889)
– Research work and heat
71
Calculate Power • Def: power is the rate of doing work • Doing work at a faster rate requires more power • To increase power, increase the amount of work done in a given time OR do a
given amount of work in less time • Power = Work/Time • The unit of work is joules (J) • The unit of time is seconds (s) • J/s = watts (W) & the unit of power is watts
What is Power? • Rate of doing work • More power = work at a faster rate
– Size of engine often indicates power • Can work at a faster rate
• Power = Work/Time – P= W/t – Watt (W) = SI unit for Power
• Units: W = J/s
James Watt and Horsepower • Horsepower (hp) = another unit for power
– Equals ~746 watts – Defined by James Watt (1736- 1819)
• Trying to describe power outputs of steam engines – Horses were most common used source of power in 1700s – Watt did not want to exaggerate the power of steam engines
The horse-drawn plow and the gasoline-powered engine are both capable of doing work at a rate of four horsepower.
72
• In which of the following cases is work being done on an object? • pushing against a locked door • suspending a heavy weight with a strong chain
• pulling a trailer up a hill • carrying a box down a corridor
Work and Machines • Objectives: • 1. Describe what a machine is and how it makes work easier to do • 2. Relate work input of a machine to work output of the machine
What a Machine is & How it Makes Work Easier
• Def: a machine is a device that changes a force • Machines make work easier to do • Machines change the size of a force needed, the direction of the force, or the
distance over which a force acts • Some machines increase distance over which to exert a force, decreasing the
amount of force needed • Some machines exert a large force over a short distance • Some machines change the direction of the applied force
Work Input and Work Output • Because of friction, the work done BY a machine is always less than the work done
ON a machine • Def: work input is work done by the input force acting through input distance • Def: work output is force exerted by a machine • Def: output distance is the distance of the output force
Machines Do Work
• Machine – device that change force – Car jack
• You apply force → jack changes force applies much stronger force to lift car
• Jack increase force you exerted – Make work easier – Change size of force needed, direction of force, and distance over which
force acts • Increasing Force
– Small force exerted over a large distance = large force over short distance • Like picking books up one at a time to move them --- trade off = more
distance but less force • Increasing Distance
• Decreases distance for force exerted and increases amount of force required
• Tradeoff = increased distance = greater force exerted
• Changing Direction
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Work Input and Work Output
• Work input to a Machine – Input Force – Force you exert on a machine
• Oar = force exerted on handle – Input Distance – Distance the input force act thru
• How far handle moves – Work Input – work done by the input force
• F x d • Work Output of a Machine
– Output Force- force exerted by machine – Output Distance – distance moved – Work output – F x d
• Less than input work b/c of friction • All machines use some input work to overcome
Work and Machines
Mechanical Advantage and Energy Objectives: 1. Compare a machine’s actual mechanical advantage to it ideal mechanical advantage 2. Calculate the ideal and actual mechanical advantages of various machines 3. Explain why efficiency of a machine is always less than 100% 4. Calculate a machine’s efficiency
Actual and Ideal Mechanical Advantage + Calculations
• Def: mechanical advantage is the number of times that a machine increases an input force
• Actual MA = output force/input force • Def: ideal mechanical advantage is the MA in the absence of friction • Friction is always present, so the actual MA of a machine is always less than the
ideal MA • Ideal MA= input distance/output distance • There are no units with MA
Key Vocabulary ● Mechanical Advantage- the ratio of the force produced by a machine to the force
applied to it, used in assessing the performance of a machine. ● Actual Mechanical Advantage-Actual mechanical advantage takes into account
energy loss due to deflection, friction, and wear. The AMA of a machine is calculated as the ratio of the measured force output to the measured force input.
● Ideal Mechanical Advantage-Chains and belts dissipate power through friction, stretch and wear, which means the power output is actually less than the power input, which means the mechanical advantage of the real system will be less than that calculated for an ideal mechanism.
● Efficiency-the state or quality of being efficient Efficiency Calculation & Why it is Less Than 100%
74
Def: efficiency of a machine is the percentage of work input that becomes work output • Efficiency is always less than 100% since friction is always present • Efficiency = work output/work input x 100%
Why do We need Mechanical Advantage ● It gives us which simple machine and/ or Compound Machine works better for
certain jobs ● Like a pulley would require less energy than a lever to lift something heavy high
off the ground Simple Machines
Objectives: 1. Describe the six types of simple machines 2. Explain what determines the mechanical advantage of the six types of simple machines
Six Types of Simple Machines & MA
• The six types of simple machines are the lever, wheel and axle, inclined plane, wedge, screw and pulley
● Lever- a rigid bar resting on a pivot, used to help move a heavy or firmly fixed load with one end when pressure is applied to the other.
● Fulcrum-the point on which a lever rests or is supported and on which it pivots. ● input arm-distance between fulcrum and input force ● output arm-distance between output force and fulcrum
Def: the output arm is the distance between the output force and the fulcrum • For a lever: MA = input arm/output arm • There are 3 classes of levers: first, second and third class • For first class levers the fulcrum is located between the input force and the output
force • MA for first class levers is =, < or > 1 • Examples: seesaws, scissors, tongs, screwdriver • For second class levers, the output force is located between the input force and
fulcrum • MA is always >1 for second class levers • Example: wheelbarrow • For third class levers, the input force is located between the fulcrum and output
force • MA is always <1 for third class levers • Examples: baseball bats, hockey sticks, golf clubs & brooms Def: a wheel and axle consists of 2 disks or cylinders, each one with a different radius • Example: steering wheel • To calculate MA for wheel and axle, divide the radius (or diameter) where the input
force is exerted by the radius (or diameter) where the output force is exerted Def: an inclined plane is a slanted surface along which a surface moves an object to a different elevation
75
• Example: ramp in front of buildings • The ideal MA for an inclined plane is the distance along the plane divided by its
height Key Vocabulary Chapter 14
Def: wheel and axle- a simple lifting machine consisting of a rope that unwinds from a wheel onto a cylindrical drum or shaft joined to the wheel to provide mechanical advantage. Def: inclined plane-a plane inclined at an angle to the horizontal. Def: wedge-a piece of wood, metal, or some other material having one thick end and
tapering to a thin edge, that is driven between two objects or parts of an object to secure or separate them.
Def: a wedge is V-shaped object whose sides are two inclined planes sloped toward each other
• Example: flat head screwdriver • A thin wedge of given length has a greater ideal MA than a thick wedge of the
same length Def: a screw is an inclined plane wrapped around a cylinder • Screws with threads closer together have a greater ideal MA Def: a pulley consists of a rope that fits into a groove in a wheel • The MA of a pulley or pulley system is equal to the number of rope sections
supporting the load being lifted Def: a fixed pulley is a wheel attached in a fixed location • The ideal MA of a fixed pulley is always 1 Def: a movable pulley us attached to the object being moved • The ideal MA of a movable pulley is 2 Def: a pulley system is a combination of fixed and movable pulleys that operate together • MA depends on pulley arrangement Def: a compound machine is a combination of two or more simple machines that operate together • Examples: cars, washing machines, clocks
Simple Machines ● lever ● Fulcrum ● Wheel and Axle ● wedge
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Simple Machines
● pulley ● inclined plane
What is a Compound Machine ● Dictionary Definition- Two or more simple machines working together to make
work easier. ● These are things such as Cars, Planes, Electrical circuits, etc. ● While the Atom is the basic building block of life with out simple machines man
would have never achieved... o Space Travel o Civilization o Cars/Easier ways of land bound travel o Flight o Or Even long lives
What can happen when simple machines come together
One good example of a compound machines is the Catapult because its the first real compound machine aside from boats with sails.
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Name __________________________________- Date _____________________- Block _______
Pearson Prentice Hall
Work, Power and Machines
• Objectives:
• 1. Describe the conditions that must exist for a force to do work on an object
• 2. Calculate the work done on an object
• 3. Describe and calculate power
• 4. Compare units of watts and horsepower as they relate to power
Work and Power
• __________– done when a __________ acts on an object in the direction the object __________
– Requires __________
• Man is not actually doing __________ when holding barbell above his __________
• __________is applied to __________
• If no movement, __________ work done
Work and Power
Work Depends on Direction
• All of the __________ does work on the suitcase.
• The horizontal part of the force does __________
• The force does __________ work on the suitcase.
Conditions for Work
• Def: __________ is the product of __________times __________
• For a __________ to do work on an object, some of the __________must act in the same direction
as the object moves
• If the object does not move, no work is done
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• Work depends on direction
• Any part of a __________ that does not act in the direction of motion does no work on the object
Calculating Work
• __________ = __________ x __________
• The units for __________ are _____________, N • Recall from chapter 12 that 1 N = 1 kg*m/s2
• The unit for distance is the __________,m
• The unit for __________ is 1 N*m or 1 kg*m2/s2 which equals one __________, abbreviated J
• Work = __________ x __________
– W = Fd
• __________ = mass x acceleration → F = ma or F = mg
– __________ (J) = SI unit for work
• Unit: J = N(m)
• Named after __________ __________ __________ (1818 – 1889)
– Research work and heat
Work out this example
Example: If a model airplane exerts 0.25 N over a distance of 10m, how much will the plane expend?
Work = F x d
Calculate Power
• Def: power is the rate of doing __________
• Doing __________ at a faster rate requires
more power
• To increase __________, increase the
amount of __________done in a given time
OR do a given amount of work in less time
• __________ = __________/ __________
• The unit of work is__________ (J)
• The unit of time is__________ (s)
• J/s = __________ (W) & the unit of power is
__________
What is Power?
80
• Rate of doing __________
• More __________ = __________at a faster rate
– Size of __________ often indicates __________
• Can work at a faster rate
• __________ = __________/__________
– P= W/t
– __________W) = SI unit for __________
• Units: W = J/s
James Watt and Horsepower 14.1
• ___________________ (hp) = another unit for __________
– Equals ~__________ watts
– Defined by __________ __________ (1736- 1819)
• Trying to describe power outputs of __________ __________
– __________were most common used source of power in 1700s
– Watt did not want to exaggerate the power of __________ __________
The __________-__________ plow and the __________ -__________ engine are both capable of doing
work at a rate of __________ horsepower.
1. In which of the following cases is work being done on an object? a) pushing against a locked door c) suspending a heavy weight with a strong chain b) pulling a trailer up a hill d) carrying a box down a corridor
2. A tractor exerts a force of 20,000 newtons to move a trailer 8 meters. How much work was done on the trailer?
a. 4,000 J b. 2,500 J c. 20,000 J d. 160,000 J
3. A car exerts a force of 500 newtons to pull a boat 100 meters in 10 seconds. How much power does the car use?
a. 5000 W b. 6000 W c. 50 W d. 1000 W
Work and Machines
81
• Objectives:
• 1. Describe what a machine is and how it makes work easier to do
• 2. Relate work input of a machine to work output of the machine
What a Machine is & How it Makes Work Easier
• Def: a __________ is a device that changes a __________
• Machines make __________ __________to do
• Machines change the size of a __________needed, the direction of the __________, or the distance
over which a force __________
• Some machines increase __________ over which to exert a __________, decreasing the amount of
__________ needed
• Some machines exert a __________ force over a __________distance
• Some machines change the __________ of the applied __________
Work Input and Work Output
• Because of __________, the work done ____ a machine is always __________than the work done
_____ a machine
• Def: work input is __________ done by the input force acting through input distance
• Def: work output is __________ exerted by a machine
• Def: output distance is the distance of the output force
Machines Do Work
• __________ – device that change force
– __________ __________
• You apply force → jack changes force applies much stronger force to lift car
• Jack increase force you __________
– Make work __________
– Change size of __________ needed, direction of force, and distance over which force
__________
• Increasing __________ • Small force exerted over a large distance = __________ force over __________
distance • Like picking books up one at a time to move them --- trade off = more distance
but less force • Increasing _____________
•Decreases distance for force ___________
and increases amount of force
_____________
•Tradeoff = increased _____________ =
greater force __________
•Changing Direction
Work Input and Work Output
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• Work input to a Machine
– __________ __________– Force you exert on a machine
• Oar = force exerted on handle
– __________ __________ – Distance the input force act thru
• How far handle moves
– __________ __________– work done by the input force
• F x d
• Work Output of a Machine
– __________ __________- force exerted by machine
– __________ __________– distance moved
– __________ output – F x d
• Less than input work b/c of __________
All machines use some __________ __________to overcome
Work and Machines
Mechanical Advantage and Energy
Objectives:
1. Compare a machine’s actual mechanical advantage to it ideal mechanical advantage
2. Calculate the ideal and actual mechanical advantages of various machines
3. Explain why efficiency of a machine is always less than 100%
4. Calculate a machine’s efficiency
Actual and Ideal Mechanical Advantage + Calculations
• Def: ________________advantage is the number of times that a machine increases an input
__________
• Actual MA = __________ __________ / __________ __________
• Def: __________ __________ advantage is the MA in the absence of __________
• __________ is always present, so the actual MA of a machine is always __________ than the ideal
MA
• Ideal MA= __________ __________ / __________ __________
• There are ______ units with MA
Key Vocabulary
● ___________________ ____________________- the _________of the force produced by a
machine to the force applied to it, used in assessing the performance of a machine.
● Actual Mechanical Advantage-Actual ___________________ ____________________takes into
account energy loss due to ___________________, ____________________ and wear. The AMA
of a machine is calculated as the __________of the measured force output to the measured force
input.
● _______ ____________ ____________________ - Chains and belts dissipate power through
____________, ____________ and ____________, which means the power output is actually less
than the power input, which means the ____________ ____________of the real system will be
____________ than that calculated for an____________mechanism.
● _______________________-the state or quality of being efficient
Efficiency Calculation & Why it is Less Than 100%
• Def: ____________of a machine is the percentage of work ____________ that becomes work
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____________
• Efficiency is always less than ____________since ____________is always present
• Efficiency = ____________ ____________/____________ ____________ x 100%
Why do we need Mechanical Advantage?
● It gives us which simple ____________ and/ or ____________ Machine works better for certain
____________
● Like a ____________ would require ____________ energy than a ____________ to lift something
____________ high off the ground
Simple Machines
Objectives:
1. Describe the six types of simple machines
2. Explain what determines the mechanical advantage of the six types of simple machines
Six Types of Simple Machines & MA
• The six types of simple machines are the ____________, ____________ and ____________,
inclined ____________, ____________, ____________ and ____________
● ____________- a rigid bar resting on a pivot, used to help move a heavy or firmly fixed load with
one end when pressure is applied to the other.
● ____________-the point on which a lever rests or is supported and on which it pivots.
● ____________ arm-distance between ____________and input force
● ____________ arm-distance between ____________ ____________ and fulcrum
• Def: the ____________ arm is the distance between the output ____________ and the fulcrum
• For a lever: MA = ____________ ____________/____________ ____________
• There are 3 classes of levers: ____________, ___________and____________class
• For first class levers the fulcrum is located between the input force and the output force
• MA for first class levers is =, < or > 1
• Examples: ____________, ____________, ____________, ____________
• For ____________ class levers, the output force is located ____________ the input force and
fulcrum
• MA is always ____________ for ____________ class levers
• Example: ____________
• For ____________ class levers, the input force is located between the ____________ and
____________force
• MA is always ______ for third class levers
• Examples: ____________ ____________, ____________ ____________, ____________
____________& ____________
• Def: a ____________ and ____________consists of _____ disks or ____________, each one with a
different ____________
• Example: ____________ ____________
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• To calculate MA for wheel and axle, divide the ____________ (or diameter) where the input force is
exerted by the____________ (or diameter) where the output force is ____________
• Def: an____________plane is a ____________ ____________along which a surface moves an
object to a ____________ ____________
• Example: _____________________________________________________________
• The ideal MA for an inclined plane is the ____________along the plane ____________ by its
____________
Key Vocabulary Chapter 14
Def: ____________ & ____________ -a simple lifting machine consisting of a rope that unwinds from a
wheel onto a cylindrical drum or shaft joined to the wheel to provide mechanical advantage.
Def: ____________ ____________-a plane inclined at an angle to the horizontal.
Def: ____________-a piece of wood, metal, or some other material having one thick end and tapering to
a thin edge, that is driven between two objects or parts of an object to secure or separate them.
Def: a ____________ is _____-shaped object whose sides are____________inclined planes
____________ toward each other
• Example: ________________________________
• A ____________ wedge of given length has a ____________ ____________ MA than a thick wedge
of the same length
Def: a ____________is an ____________ plane wrapped around a ____________
• Screws with ____________ closer together have a ____________ ideal MA
Def: a ____________ consists of a ____________ that fits into a ____________ in a ____________
• The MA of a pulley or pulley system is equal to the number of ____________ ____________
supporting the ____________being lifted
Def: a fixed____________is a wheel attached in a____________location
• The ideal MA of a fixed pulley is always_____
Def: a ____________ pulley us attached to the object being ____________
• The ideal MA of a movable pulley is ____
Def: a ____________ ____________is a combination of fixed and movable ____________ that operate
____________
• MA depends on ____________ ____________________
Def: a ____________ ____________ is a combination of two or more____________ machines that
operate together
• Examples: ________________________________________________
Simple Machines
● lever
● Fulcrum
● Wheel and Axle
● Wedge
Simple Machines
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● pulley
● inclined plane
What is a Compound Machine
● Dictionary Definition- Two or more ____________ ____________working ____________ to
make work ____________
● These are things such as ________________________________________________
● While the Atom is the basic building block of life without ____________ machines man would
have never achieved...
o ____________ ____________
o ____________
o Cars/Easier ways of land bound travel
o ____________
o Or Even long lives
What can happen when simple machines come together…..
One good example of a compound machines is the ________________________because it’s the first real
compound machine aside from boats with sails.
If you think you could make a catapult, do so. Then video it and send it to me!
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Test #
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14
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ship
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nau
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14
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neg
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87
88
Nam
e ______
______
_____
______
______
_____
_______
Date __
____
____
______
____ B
lock __
____
__ Test # ____
____
(Fill this in
!!)
Ty
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refix, R
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or S
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89
90
How Many Horses? It was the late 1800’s, and engineer James Watt was stumped. He’d just figured out a way to make
steam engines operate much more efficiently. He wanted to start manufacturing and selling his new
invention. But how could he describe how powerful these amazing engines were?
Watt’s answer? Compare the power of the steam engine with something that people were very
familiar with: the power of a horse.
In Watt’s day, ponies (small horses) were used to pull ropes attached to platforms that lifted coal
to the surface of the earth from the mine below. Watt measured how much these loads weighed (force).
Then he determined how far the ponies could raise them (distance) in one minute (time). Using these
measurements, he calculated how much work a pony could do in a minute – he calculated the power of a
pony – ponypower!
At that time, the unit of work used by British scientists was the foot-pound (ft-lb). On the basis of
his observations and calculations, Watt found that a pony could do 22,000 ft-lb of work a minute.
Because he figured that the average horse was as powerful as 1.5 ponies, he multiplied the power of one
pony (22,000 ft-lb of work per minute) by 1.5 and called it 1 horsepower (hp).
In other words, 1 hp is equal to 33,000 ft-lb of work per minute, or 550 ft-lb of work per second.
This means that an average horse can lift a 550-lb load a distance of 1 foot in 1 second.
Horsepower can be translated into watts (W): 1 hp equals 746 W. A 350-hp engine, therefore,
has the same power as a 261,100-W engine. But when numbers get as big as this, you can see that watts
aren’t a convenient way of expressing the power of engines. So, the term “horsepower” stuck around.
Using the word “horsepower” also probably makes drivers feel closer to the old days – when people were
pioneers and mustangs were horses!!
91
Name ______________________________________________ Date _______________ Period _________
1. Why do you think James Watt used a horse as a measure of a unit of power?
_________________________________________________________________________________________________________________
2. How did Watt decide the value of 1 horsepower?
_________________________________________________________________________________________________________________
3. Why is “horsepower” still a useful unit of power?
_________________________________________________________________________________________________________________
4. How many Watts make up 1 hp? ______________________________________________
5. How long did it take a horse to lift 550 lb a distance of 1 ft, according to Watt? ___________
6. Calculate the following common horsepower ratings to watts
Machine Horsepower rating
(average for category) Convert to Watts by multiplying by 746
Electric toothbrush .08 HP
Low-capacity clothes dryer .33 HP
Household Blender .5 HP
Vacuum cleaner 1.25 HP
Moped 2 HP
Lawn mower 4.5 HP
Gasoline generator 10 HP
BMW police motorcycle 95 HP
Ford Escort 110 HP
Yamaha Jet Ski 155 HP
Coral Viper Ski Boat 250 HP
Ferrari 355 F1 375 HP
Dodge Viper 450 HP
MAN Yacht Engine 1,050 HP
Battleship Missouri 212,000 HP
92
Name __________________________________ Date: _____________ Block ________________
Information: Calculating Power
In the scientific community, power is only used if work is done on an object in a certain amount of time. To
calculate the power used on an object, the work done on the object is divided by the time it took to do the work.
Power involves both work and time.
So, how much power did you do on that book bag you lifted onto the desk? It’s not hard to figure out. First find
the work you did on the book bag. Multiply the force needed to lift the bag by the distance the object as lifted.
Here’s an example of how to calculate power – you always have to calculate work FIRST if you don’t have it!
Michael lifts his book bag, which weighs 25 N, from the floor to a desktop that is 0.80 m above the floor. It takes
him 5 s to lift the book bag. How much power does Michael use?
Work = Force x Distance
Work = 25 N x 0.80 m
Work = 20.0 J
Michael does 20.0 J of work on the book bag.
Then divide the work by the time it took to lift the book bag.
time
WorkPower =
s
JPower
5
0.20=
Power = 4 J/s or W
Work is measured in Joules (J) and time is in measured in seconds (s). When dividing the two to find Power, we
end up with Joules per second (J/s). A Joule per second (J/s) is also called a Watt (W). Power is measured in
Watts (W).
Power Problems - These include Power (W) , Work (J) and Time (s)
You will need BOTH the work and power triangle for these
Directions: Use your knowledge of power and work to answer the following problems. Make sure to show all
work and include all units.
1. Dante uses 14 J of work to lift a weight for 30 seconds. How much power did he use?
Givens Solving For
Equation Substitution Answer with Units
W = 14 J T = 30 s Power
P = W/T P = 14/30 0.47 W
93
2. A machine produces 4000 Joules of work in 5 seconds. How much power does the machine produce?
Givens Solving For
Equation Substitution Answer with Units
3.If it took Mr. Youngbauer 37 seconds to lift a 400 N student up 15 m, how much work and power did he use?
a. solve for work (w = f * d)
Givens Solving For
Equation Substitution Answer with Units
4. b. solve for power – Using the work you calculated above.
Givens Solving For
Equation Substitution Answer with Units
5. Darth Vader unleashed the power of the dark side (1225 W) on the unsuspecting Jedi. If he did 727 J of
work, how much time did it take?
Givens Solving For
Equation Substitution Answer with Units
6. A person weighing 600 N gets on an elevator. The elevator lifts the person 6 m in 10 seconds. How
much power was used? You MUST calculate work FIRST! Work = force x distance
a. calculate work
Givens Solving For
Equation Substitution Answer with Unit
7. calculate power – Using the work you calculated above.
Givens Solving For
Equation Substitution Answer with Units
94
8. How much time is needed to produce 720 Joules of work if 90 watts of power is used?
Givens Solving For
Equation Substitution Answer with Units
9. If 68 W of power is produced in 18 seconds, how much work is done?
Givens Solving For
Equation Substitution Answer with Units
10. A set of pulleys lifts an 800 N crate 4 meters in 7 seconds. How much work was there?
Givens Solving For
Equation Substitution Answer with Units
11. What power was used? – Using the work you calculated above.
Givens Solving For
Equation Substitution Answer with Units
12. Superman moves a car 2700 N on a track of 500 m. If the car takes 32 seconds to move the entire distance,
how much work is needed? W= F * d
Givens Solving For
Equation Substitution Answer with Units
13. how much (super)power is exerted by Superman? – Using the work you calculated above.
Givens Solving For
Equation Substitution Answer with Units
95
14. Superman is unhappy with his time in the above problem, so he attempts to lift the same car. This time, it
takes 18.1 seconds. How much does his power increase?
Givens Solving For
Equation Substitution Answer with Units
15. Mrs. VerHeecke can bench press 150 kg from 0.7 m from the ground to 1.5 m above the ground.
How much weight (not mass) did Mrs. VerHeecke lift? This is the W = mass * gravity (gravity is 9.8)
Givens Solving For
Equation
W = m * g
Substitution Answer with Units
16. How much work was needed? – Using the weight (which is a force) you calculated above (subtract 1.5-0.7)
Givens Solving For
Equation Substitution Answer with Units
17. How much power did she use if she lifts the weights in 10s? – Using the work you calculated above.
Givens Solving For
Equation Substitution Answer with Units
18. Marc is completing a task that requires 400 J. His power is 40 W. How long will it take Marc to complete
the task?
Givens Solving For
Equation Substitution Answer with Units
19. A small motor does 4000 J of work in 20 seconds, what is the power of the motor in Watts?
Givens Solving For
Equation Substitution Answer with Units
96
20. How much power does a crane develop, doing 60000 J of work in 5 minutes? Change min to seconds!
5 minutes X 60 seconds = ___________ seconds
1 1 minute
Givens Solving For
Equation Substitution Answer with Units
21. How long does it take a 2000W electric motor to do 75000 J of work?
Givens Solving For
Equation Substitution Answer with Units
22. How much work can a 500 W electric mixer do in 2.5 minutes? Minutes has to be changed to seconds!
_________ X 60 seconds = ___________ seconds
1 1 minute
23. How much work does a 100 W motor perform in 5 minutes? Minutes has to be changed to seconds!
_________ X 60 seconds = ___________ seconds
1 1 minute
24. How long does it take a 19,000 W steam engine to do 68000000 J of work
Givens Solving For
Equation Substitution Answer with Units
Givens Solving For
Equation Substitution Answer with Units
Givens Solving For
Equation Substitution Answer with Units
97
25. How much work is done using a 500-watt microwave oven for 5 minutes (minutes has to change to sec)
_________ X 60 seconds = ___________ seconds
1 1 minute
26. How much work is done using a 60-watt light bulb for 1 hour? (hours has to change to seconds)
_________ X 60 minutes X 60 seconds = ___________ seconds
1 1 hour 1 minute
27. Frank does 2400J of work in climbing a set of stairs. If he does the work in 6 seconds, what is his power
output?
28. A 750 watt hairdryer is used for 60 seconds. How many joules of energy (how much work) are used?
29. If you are climbing a flight of stairs and it takes you 1000 J of work and 25 Watts of power, how long did it
take you to climb the stairs?
Givens Solving For
Equation Substitution Answer with Units
Givens Solving For
Equation Substitution Answer with Units
Givens Solving For
Equation Substitution Answer with Units
Givens Solving For
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Givens Solving For
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98
30. A student weighing 400 N climbs a 3 m ladder in 4 sec.
First… calculate how much work is done
31. Now…calculate how much power – Using the work you calculated above.
32. A figure skater lifts his partner, who weighs 450 N a height of 1 m in 3 sec. How much work is required to
lift the skater?
33. How much power is required to lift the skater? – Using the work you calculated above.
34. A 500 N passenger is inside a 24,000 N elevator that rises 30 m in exactly 60 sec. How much power is
needed for the elevator’s trip? You have to add something together to get started!!!
First you have to calculate the work
35. Now you calculate the power – Using the work you calculated above.
Givens Solving For
Equation Substitution Answer with Units
Givens Solving For
Equation Substitution Answer with Units
Givens Solving For
Equation Substitution Answer with Units
Givens Solving For
Equation Substitution Answer with Units
Givens Solving For
Equation Substitution Answer with Units
Givens Solving For
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99
36. If you are climbing a flight of stairs and it takes you 1000 J of work and 200 Watts of power, how long did it
take you to climb the stairs?
37. How much work & power is needed for a person weighing 500 N to climb a 3 m ladder in 5 sec.?
Calculate the work
Givens Solving For
Equation Substitution Answer with Units
38. Calculate the power – Using the work you calculated above.
Givens Solving For
Equation Substitution Answer with Units
39. A student lifts a 0.15 kg sandwich 0.3 m from the table in 2 sec. How much work does she do? You have to
calculate weight first… w = m x g (9.8) to get newtons, then calculate work
So…calculate the weight
Givens Solving For
Equation Substitution Answer with Units
N
40. Now calculate the work – Using the weight (which is a force) you calculated above
Givens Solving For
Equation Substitution Answer with Units
41. Then calculate the power – Using the work you calculated above.
Givens Solving For
Equation Substitution Answer with Units
Givens Solving For
Equation Substitution Answer with Units
100
42. How long will it take a 500 Watt motor to do 6000 J of work?
Givens Solving For
Equation Substitution Answer with Units
43. How long did it take to lift a box that you used 36 W of power and exerted 72 J of work to lift?
Givens Solving For
Equation Substitution Answer with Units
44. You lift a large bag of flour from the floor doing 100 J of work and exerting 50 Watts of power. How long
did it take you to lift the bag?
Givens Solving For
Equation Substitution Answer with Units
45. If you exert 50 Watts of power and use 3000 J of work to lift a piano up, how long did it take you to lift the
piano?
Givens Solving For
Equation Substitution Answer with Units
46. If you exert 70 Watts of power and use 350 J of work push a box along the floor, how long did it take you to
lift the piano?
Givens Solving For
Equation Substitution Answer with Units
101
Hulky and Bulky are two workers being considered for a job at the UPS loading dock. Hulky boasts that he can
lift 100 kg box 2.0 m vertically in 3.0 seconds. Bulky counters with his claim of lifting a 200 kg box 5.0 m
vertically in 20 seconds. Which worker do you think has a greater power rating?
47. Hulky (3 steps) calculate weight
Givens Solving For
Equation Substitution Answer with Units
48. calculate work – Using the weight (which is a force) you calculated above
Givens Solving For
Equation Substitution Answer with Units
49. calculate power
Givens Solving For
Equation Substitution Answer with Units
50. Bulky (3 steps) a. calculate weight
Givens Solving For
Equation Substitution Answer with Units
51. calculate work – Using the weight (which is a force) you calculated above
Givens Solving For
Equation Substitution Answer with Units
52. calculate power – Using the work you calculated above.
Givens Solving For
Equation Substitution Answer with Units
102
53. Which worker has a greater power rating? A. Hulky B. Bulky C. both are the same
You and a friend run upstairs that are 30 m high. Both of you reach the top in 12 seconds. You weigh 570 N and
your friend weighs 620 N. Which one of you has more power do you think?
54. You - calculate work W = F * d or in other words Joules
Givens Solving For
Equation Substitution Answer with Units
55. Calculate Power – Using the work you calculated above.
Givens Solving For
Equation Substitution Answer with Units
56. Your Friend - calculate work W = F * d or in other words Joules
Givens Solving For
Equation Substitution Answer with Units
57. Calculate Power - Using the work you calculated above.
Givens Solving For
Equation Substitution Answer with Units
58. Which one of you has more power? A. You do B. Your friend does C. both of us are the same
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104
Name _______________________________ Answer Sheet for Power
____1. a. 0.47
____2. a. 20,000 b. 800 c. .00125
____3. a. 2.67 b. .0375 c. 6000
____4. a. 6.17 b. 222000 c. 162
____5. a. 1.69 b. 0.59 c. 890575
____6. a. 3600 b. 100 c. 0.01
____7. a. 0.0028 b. 3600 c. 360
____8. a. 0.125 b. 64800 c. 8
____9. a. 0.26 b. 1224 c. 3.8
____10. a. 0.0005 b. 3200 c. 200
____11. a. 0.0002 b. 22400 c. 457
____12. a. 0.185 b. 5.4 c. 1350000
____13. a. 42188 b. 2.37 x 10-5 c. 4.32 x 107
____14. a. 74,586 b. 24,435,000 c. 1.34 x 10-5
____15. a. 0.0065 b. 15.3 c. 1470
____16. a. 19.125 b. 1176 c. 1.22
____17. a. 0.82 b. 122 c. 1.22
____18. a. 0.1 b. 16000 c. 10
____19. a. 0.0005 b. 200 c. 80,000
____20. a. 0.005 b. 200 c. 1.8 x 107
____21. a. 0.0027 b. 37.5 c. 1.5 x 108
____22. a. 0.003 b. 3.3 c. 75,000
____23. a. 0.0033 b. 3 c. 30,000
____24. a. 3579 b. 0.0003 c. 1.292 x 1012
____25. a. 1.67 b. 150,000 c. 0.6
____26. a. 1.67 b. 60 c. 21,6000
____27. a. 0.0025 b. 14,000 c. 400
____28. a. 45,000 b. 12.5 c. 0.08
____29. a. 25,000 b. 0.025 c. 40
____30. a. 0.0075 b. 133 c. 1200
____31. a. 300 b. 4800 c. 0.003
____32. a. 450
____33. a. 0.007 b. 1350 c. 150
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____34. a. 0.0012 b. 816.7 c. 735,000
____35. a. 8.1 x 10-5 b. 4.41 x 107 c. 12,250
____36. a. 2.0 x 105 b. 5 c. 0.2
____37. a. 0.006 b. 167 c. 1500
____38. a. 300 b. 3 c. 7500
____39. a. 0.51 b. 1.47 c. 4.9
____40. a. 0.441 b. 1.47 c. 4.9
____41. a. 0.2205 b. 1.02 c. 0.3
____42. a. 0.083 b. 12 c. 3.0 x 106
____43. a. 0.5 b. 2592 c. 2
____44. a. 0.5 b. 2 c. 5000
____45. a. 1.5 x 106 b. 0.167 c. 60
____46. a. 5 b. 24,500 c. 0.2
____47. a. 10.20 b. 980 c. 1960
____48. a. 1960 b. 490 c. 980
____49. a. 5880 b. 653 c. 1960
____50. a. 20.4 b. 0.49 c. 1960
____51. a. 9800 b. 392 c. 653
____52. a. 9800 b. 490 c. 1960
____53. a. Hulky b. Bulky c. both are the same
____54. a. 1550 b. 1417 c. 17,100
____55. a. 1550 b. 1425 c. 17,100
____56. a. 18,600 b. 1550 c. 1425
____57. a. 18,600 b. 1550 c. 1417
____58. a. You do b. Your friend does c. both of us are the same
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Name ____________________________________ Date ____________
Information: Calculating Work
In the scientific community, work is only done if a force is applied to an object and that object moves a
distance. To calculate the work done on an object, the force that pushes or pulls on the object is multiplied by
the distance the object moves. Work involves both force and distance AND they have to be in the SAME
direction!
So, how much work did you do on that book bag you lifted onto the desk? It’s not hard to figure out. Multiply
the force needed to lift the bag by the distance the object as lifted. That’s it! In other words: Work = Force x
Distance
Force is measured in Newtons (N) and distance in measured in meters (m). When multiplying the two to find
Work, we end up with a Newton-meter (N*m). A Newton-meter is also called a Joule (J). Work is measured in
Joules (J), for James Joule, who made important discoveries about work and energy.
Here’s an example of how to calculate work:
Michael lifts his book bag, which weighs 25 N, from the floor to a desktop that is 0.80 m above the floor. How
much work does Michael do on the bag?
Work = Force x Distance
Work = 25 N x 0.80 m
Work = 20.0 J
Michael does 20.0 J of work on the book bag.
Work Problems Directions: Make sure to show all work and include all units.
1. A person pushes a block 4 m with a force of 24 N. How much work was done?
Givens Solving For
Equation Substitution Answer with Units
2. Paul Konerko hit a 125 m grand slam in Game 2 of the World Series. He did 3000 J of work. With
what force did he hit the ball?
Givens Solving For
Equation Substitution Answer with Units
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3. A person does 15 J of work moving a couch 1.3 m. How much force was used?
Givens Solving For
Equation Substitution Answer with Units
4. You lift a box that weighs 50 N to a height of 1.7 m. How much work did you do on the box?
Givens Solving For
Equation Substitution Answer with Units
5. A 750 N skydiver jumps out of an airplane that is flying at an altitude of 2800 m. By the time the
skydiver reaches the ground, how much work was done on her by gravity?
Givens Solving For
Equation Substitution Answer with Units
6. A bulldozer performs 75,000 J of work pushing dirt 18 m. What is the force exerted?
Givens Solving For
Equation Substitution Answer with Units
7. How much work is done when a 10 N force moves an object 2.5 m?
Givens Solving For
Equation Substitution Answer with Units
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8. If Ms. Vandersee holds a mass of 55 kilograms and climbs up stairs that are 30 meters tall then how
much work was done? First you have to get Newtons by multiplying mass times gravity
Givens Solving For
Equation Substitution Answer with Units
9. Now that you have the force, calculate the work
Givens Solving For
Equation Substitution Answer with Units
10. If 68 Joules of work were necessary to move a 4 Newton crate, how far was the crate moved?
Givens Solving For
Equation Substitution Answer with Units
11. If a group of workers can apply a force of 1000 Newtons to move a crate 20 meters, what amount of
work will they have accomplished?
Givens Solving For
Equation Substitution Answer with Units
12. How much work is done when an 8 N force moves a block 7m?
Givens Solving For
Equation Substitution Answer with Units
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13. How far will 490 J of work raise a block weighing 7 N?
Givens Solving For
Equation Substitution Answer with Units
14. Eva applies 40 N force to move her bookcase 3 m, how much work did Eva do?
Givens Solving For
Equation Substitution Answer with Units
15. Shelia did 110 J of work to move a chair 2 m to the right. How much force did Shelia use to move the
chair?
Givens Solving For
Equation Substitution Answer with Units
16. A force of 800 Newtons is needed to push a car across a lot. Two students push the car 40 meters. How
much work is done?
Givens Solving For
Equation Substitution Answer with Units
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17. How much work is done in lifting a 60Kg crate a vertical distance of 10 meters? You have to calculate
weight first (remember w=m*g where g stands for gravity of 9.81 m/s2)
Weight
Givens Solving For
Equation
Substitution Answer with Units
18. Now that you have calculated the weight, you have a force so now you can calculate work.
work
Givens Solving For
Equation Substitution Answer with Units
19. Amy uses 20 N of force to push a lawn mower 10 meters How much work will she do?
Givens Solving For
Equation Substitution Answer with Units
20. How much work does an elephant do while moving a circus wagon 20 meters with a pulling force of 200N?
Givens Solving For
Equation Substitution Answer with Units
21. A 1000 N mountain climber scales a 100 m cliff. How much work is done?
Givens Solving For
Equation Substitution Answer with Units
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22. Calculate the work, pushing with 115 N over 15m
Givens Solving For
Equation Substitution Answer with Units
23. Calculate the work - lifting 20 N over 10 m
Givens Solving For
Equation Substitution Answer with Units
24. If 100 J of work are done by lifting a box 1.5 m, then how much mass was the box?
First you have to calculate the force…
Givens Solving For
Equation Substitution Answer with Units
25. Then you can calculate the mass because Newtons is also equal to mass * gravity so m=N/g
Givens Solving For
Equation Substitution Answer with Units
26. A 900N mountain climber scales a 100m cliff. How much work is done by the mountain climber? Givens Solving For
Equation Substitution Answer with Units
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27. Shawn uses 45N of force to stop the cart 1 meter from running his foot over. How much work does he do?
Givens Solving For
Equation Substitution Answer with Units
28. How much work is done when a force of 33N pulls a wagon 13 meters?
Givens Solving For
Equation Substitution Answer with Units
29. How much work is required to pull a sled 5 meters if you use 60N of force?
Givens Solving For
Equation Substitution Answer with Units
30. Tommy does 15 Joules of work to push the pencil over 1 meter. How much force did he use?
Givens Solving For
Equation Substitution Answer with Units
31. Angela uses a force of 25 Newtons to lift her grocery bag while doing 50 Joules of work. How far
did she lift the grocery bags? Givens Solving For
Equation Substitution Answer with Units
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32. Calculate the work done by a 47 N force pushing a pencil 0.26 m.
Givens Solving For
Equation Substitution Answer with Units
33. Calculate the work done by a 47 N force pushing a pencil 0.25 m against a force of 23 N. (Hint: you have to subtract
something here before you get started!) Givens Solving For
Equation Substitution Answer with Units
34. How much work is it to lift a 20 kg sack of potatoes vertically 6.5 m? You have to calculate weight first
(remember w=m*g where g stands for gravity of 9.81 m/s2) so that you have a force so you can calculate work.
Givens Solving For
weight
Equation
Substitution Answer with Units
35. Now using the weight you calculated above, determine how much work is needed
Givens Solving For
Equation Substitution Answer with Units
36. A winch does 40,000 J of work lifting a beam 15.3 m. Determine the force.
Givens Solving For
Equation Substitution Answer with Units
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37. How heavy is the beam? Use the force from above to calculate the mass. Givens Solving For
Equation Substitution Answer with Units
38. Compute the work done when a force of 500 N is used to life a crate 2.4 meters
Givens Solving For
Equation Substitution Answer with Units
39. A car engine exerts a force of 1000 N while moving the car 200 m. How much work is done?
Givens Solving For
Equation Substitution Answer with Units
40. How much work have you done if you used 2N of force and lifted a box 1 meter off the floor?
Givens Solving For
Equation Substitution Answer with Units
41. How much work would it take to push a grocery cart full of groceries if you used 2N of force and made
it go 12 meters?
Givens Solving For
Equation Substitution Answer with Units
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42. How much force would a team of dog sled dogs have to apply to a sled to move it 30 meters & do 300 J
of work?
Givens Solving For
Equation Substitution Answer with Units
43. If a car is moved 10 meters & 3 N of force is needed to move the car, what amount of work has been done? Givens Solving For
Equation Substitution Answer with Units
44. If a ball is lifted 2 meters off the ground and 5 Newtons of force were needed to move it, what amount of
work has been done? Givens Solving For
Equation Substitution Answer with Units
45. The force required to move a chair 4 meters is 3 Newtons, what amount of work is done? Givens Solving For
Equation Substitution Answer with Units
46. You decided to change your bedroom. You move your bed 1.5 m across your room and the force you used
to move the bed was 20 N, how much work did you do? Givens Solving For
Equation Substitution Answer with Units
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47. If you are in a car that is being pulled down a 56.0 m path with a force of 12.5 Newton’s (N), what is
the “work” done on the car?
Givens Solving For
Equation Substitution Answer with Units
48. A crane does work of 13,500 J with a force of 5200 N to lift a beam. How far can the beam be lifted?
Givens Solving For
Equation Substitution Answer with Units
49. A force of 100 N was necessary to lift a rock. A total of 150 joules of work was done. How far was the rock lifted?
Givens Solving For
Equation Substitution Answer with Units
50. It took 500 N of force to push a car 4 meters. How much work was done?
Givens Solving For
Equation Substitution Answer with Units
51. It took 50 J to push a chair 5 m across the floor. With what force was the chair pushed?
Givens Solving For
Equation Substitution Answer with Units
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52. You exerted 85 J of work on a box that weighs 50 N. How far did you lift it? Givens Solving For
Equation Substitution Answer with Units
53. How much work is done when a 30 N force moves an object 8 m?
Givens Solving For
Equation Substitution Answer with Units
54. If 56 J of work is used to exert 8 N of force on a box, how far was it able to move it?
Givens Solving For
Equation Substitution Answer with Units
55. If 429 J of work is used to pull a wagon 13m, what force was used on the wagon?
Givens Solving For
Equation Substitution Answer with Units
56. You were moving into your dorm room and didn’t like where the bookcase was. You exerted 120 J of work to move it 3m. How much force was applied to the bookcase?
Givens Solving For
Equation Substitution Answer with Units
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Name_______________________________ Date__________________
Work Problems – choose the correct answer choice and mark it on your answer sheet. If you don’t see the
correct answer, rework it to make sure you did it right! ________1. a. 6 J b. 96 J c. 0.167 J d. 96 N
________2. a. 375000 J b. 0.04167 c. 24 J d. 24 N
________3. a. 19.5 N b. 11.5 N c. 11.5 J d. 0.0867 N
________4. a. 85 N b. 85 J c. .34 J d. 2.94 J
________5. a. 3.73 J b. .268 J c. 2.1 X 106N d. 2100000 J
________6. a. 4166.7 N b. 2.4 x 10 c. 4166.7 J d. 1350000J
________7. a. .25 J b. 4 J c. 25 J d. 25 N
________8. a. 5.61 N b. 539 N c. 17.97 J d. 16170 J
________9. a. 5.61 N b. 539 N c. 17.97 J d. 16170 J
________10. a. 17 m b. 272 m c. .06 m d. 1.7 m
________11. a. 50 J b. 50 N c. 20,000 J d. .02 J
________12. a. 0.875 J b. 56 N c. 56 J d. 1.14J
________13. a. 70 N b. 3430 m c. 70 m d. 0.014 m
________14. a. 0.075 J b. 13.3 J c. 120 J d. 120 N
________15. a. 55 J b. 220 N c. 220 m d. 55N
________16. a. 20 J b. 32000 N c. 32000 J d. 20 N
________17. a. 58.86 J b. 5886 J c. 588.6 N d. 588.6 J
________18. a. 58.80 J b. 5880 J c. 588.0 N d. 588.0 J
________19. a. 2 J b. 0.5 J c. 200 J d. 200 N
________20. a. 4000N b. 400.0 J c. 4000 J d. 10 J
________21. a. 10 J b. 0.1 J c. 100,000 N d. 100,000 J
________22. a. 7.67 J b. 1725 J c. 2 J d. 200 J
________23. a. 7.67 J b. 1725 J c. 2 J d. 200 J
________24. a. 150 N b. 66.7 N c. 654 g d. 6.8 g
________25. a. 150 N b. 66.7 N c. 654 g d. 6.8 g
________26. a. 9 J b. .11 J c. 90,000 N d. 90,000 J
________27. a. 45 J b. 45 N c. 45 m d. 4.5 J
________28. a. 0.39 J b. 429 N c. 429 J d. 2.5 J
________29. a. 0.083 b. 300 J c. 12 J d. 300 N
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________30. a. 15 J b. 15 N c. 1.5 J d. 1.5 N
________31. a. 1250 m b. 0.5 m c. 2 m d. 12.50 m
________32. a. 1.222 J b. 12.22 J c. 180.8 J d. 12.22 N
________33. a. 6 N b. 96 J c. 6J d. 9.6 N
________34. a. 196.2 J b. 0 .49 J c. 2.04 J d. 196.2 N
________35. a. 1275.3 J b. 1275.3 N c. 30J d. 30N
________36. a. 2614.4 N b. 2614.4 J c. 266.5 kg d. 25647kg
________37. a. 2614.4 N b. 2614.4 J c. 266.5 kg d. 25647kg
________38. a. 1200 N b. 1200 J c. 208.33 J d. .0048 J
________39. a. 0.2 J b. 20,000J c. 200,000 J d. 5 J
________40. a. 0.5 J b. 2 J c. 0.5 N d. 2N
________41. a. 24 N b. 6 J c. 24 J d. 2.4 J
________42. a. 0.1 N b. 10 N c. 9000N d. 10 J
________43. a. 03. J b. 30 J c. 30 N d. 3.3 J
________44. a. 2.5 J b. 10 J c. 10 N d. 1.0 N
________45. a. 1.3 J b. 12 N c. 12 J d. .75 J
________46. a. 13.3 J b. 30 N c. 30 J d. 3.0 J
________47. a. 4.48 J b. 700 N c. 0.22 J d. 700 J
________48. a. 0.39m b. 2.6 m c. 2.6 N d. 70200000m
________49. a.67 m b. 1.5 N c. 1.5 m d. 15000 m
________50. a. 125 J b. 2000 N c. 2000 J d. .008 J
________51. a. 250 N b. 0.10 N c. 10 N d. 10 J
________52. a. 0.59 m b. 4250 m c. 1.7 m d. 1.7 N
________53. a. 0.267 J b. 3.75 J c. 240 N d. 240 J
________54. a. 14 m b. .14 m c. 7 m d. 448 m
________55. a. 33 J b. 557 N c. 0.03N d. 33 N
________56. a. 40 J b. 360 N c. 0.25 N d. 40 N
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Energy
Energy and Its Forms Objectives: 1. Describe and compare how energy and work are related 2. Explain what factors kinetic energy of an object depends on 3. Discuss how gravitational potential energy is determined 4. Summarize the major forms of energy
How Energy & Work are Related + Kinetic Energy
Def: energy is the ability to do work • Work is a transfer of energy Def: kinetic energy is the energy of motion • The kinetic energy of any moving object depends on its mass and speed • The formula is: KE = ½ mv2 where m = mass and v is the velocity (which must be
squared) • the units for m are kg & v = (m/s)2 or m2/s2
• the units for PE are kg*m2/s2 which is also called joules, J
Potential Energy
Def: potential energy is stored energy as a result of position or shape • PE is energy with the potential to do work • Two forms of PE are gravitational PE and elastic PE • Def: gravitational PE is PE that depends upon an object’s height • Gravitational PE increases when an object is at a higher height • An object’s gravitational PE depends on its mass, height & acceleration due to
gravity • The formula for gravitational PE = mgh where m= mass (kg), g= 9.8 m/s2 (the free
fall acceleration of gravity) & h = height in meters, m • When you multiply all the units together you get kg*9.8m/s2*m or kg*m2/s2 which is J • Def: elastic PE is the PE of an object that is stretched or compressed • An object is elastic if it springs back after being stretched
Practice Problems
• Calculate the KE of a 1500kg car moving at 29m/s. • A bowling ball traveling at 2.0m/s has 16J of KE. What is the mass of the bowling
ball in kg?
• Calculate the PE of a car with a mass of 1200kg at the top of a 42m hill. • Calculate the PE of a 55g egg held out of a 2nd story window, 6m off the ground.
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Forms of Energy • The major forms of energy are mechanical energy, thermal energy, chemical
energy, electrical energy, electromagnetic energy and nuclear energy • Def: mechanical energy is the energy associated with the motion and position of
everyday objects • Def: thermal energy is the total PE and KE of all the microscopic particles in an
object • Def: chemical energy is the energy stored in chemical bonds • Def: electrical energy is the energy associated with electric charges • Def: electromagnetic energy is a form of energy that travels through space in the
form of waves • Def: nuclear energy is the energy stored in atomic nuclei
Energy Conversion & Conservation
Objectives: 1. Describe how energy can be converted from one form to another 2. Explain the law of conservation of energy 3. Discuss the energy conversion that takes place as an object falls toward Earth 4. Discuss how energy and mass are related
Energy Can be Converted from One Form to Another • Def: energy conversion is the process of changing energy from one form to
another • Sometimes energy is converted to other forms in a series of steps • Ex: striking a match uses chemical energy from your muscles, then friction
between match and box converts KE to thermal energy, thermal energy triggers a chemical reaction releasing more chemical energy
• Often energy converts directly from one form to another • a wind up toy, for example, is PE to KE
Conservation of Energy + Energy Conversions and Gravity • The Law of Conservation of Energy states that energy cannot be created or
destroyed • The gravitational PE of an object is converted to the KE of motion as an object falls • Pendulums constantly convert PE to KE and KE to PE as the pendulum swings • At the bottom of the swing, the pendulum has maximum KE and zero PE • On either side the pendulum will have a combination of PE + KE • Q: Where is the PE the greatest and KE zero?
Energy and Mass • Mechanical energy = KE + PE • Mechanical energy is also conserved • (KE + PE)beginning = (KE + PE) end • Einstein has an equation: E = mc2 where E is energy (J), m is mass (kg) & c2 is the
speed of light squared (3 x 108 m/s)2
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• This equation says that energy and mass are equivalent and can be converted into each other
• It also means that a tiny amount of matter can produce enormous amounts of energy
• Mass and energy together are always conserved
Energy Resources3 Energy Resources
Objectives: 1. Give examples of the major nonrenewable and renewable energy sources 2. Explain how energy resources can be conserved
Nonrenewable and Renewable • Nonrenewable energy resources include oil, natural gas, coal and uranium • Oil, natural gas and coal are fossil fuels • Fossil fuels were formed underground from once living organisms • Most nonrenewable resources are considered inexpensive, available and are
known to cause pollution • Renewable energy resources include hydroelectric, solar, geothermal, wind, and
biomass • Def: hydroelectric energy is energy obtained from flowing water • Hydroelectric energy production usually involves the building of a dam • Hydroelectric is available, used today and generally nonpolluting • Def: solar energy is sunlight converted to usable energy • Solar energy is expensive and its use is limited until technology improves • Def: geothermal energy is thermal energy beneath the earth’s surface • It is nonpolluting and available in this area due to naturally occurring hot springs • most places are not near a volcano or hot springs • Def: biomass energy is the energy stored in living things • Biomass can be converted directly to thermal energy • Agricultural waste such as turning corn into ethanol for auto fuel is an example • This technology is moderately expensive • Wind energy requires a lot of land and a place that has a lot of wind • It is expensive and not practical at this time although research continues • Hydrogen fuel cells are being used in some places to generate electricity by
reacting hydrogen with oxygen • The main source of hydrogen is water • This technology is expensive and considered to be a research and development
project for future energy sources Conservation of Resources
• Energy resources can be conserved by reducing energy needs and by increasing the efficiency of energy use
• Def: energy conservation is finding ways to use less energy or use energy more efficiently
• Q: Can you think of some ways we can conserve energy resources?
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Name ________________________________ Date: _________ Block : _______
Chapter 15 - Energy
Energy and Its Forms Objectives: 1. Describe and compare how energy and work are related 2. Explain what factors kinetic energy of an object depends on 3. Discuss how gravitational potential energy is determined 4. Summarize the major forms of energy
How Energy & Work are Related + Kinetic Energy
Def: __________ is the ability to do work
• Work is a _________of _________
Def: _________ _________is the energy of _________
• The _________ _________of any moving object depends on its _________and _________
• The formula is: _________ _________ = ½ mv2 where m = mass and v is the velocity (which
must be _________)
• the units for mass are kg & v = (m/s)2 or m2/s2
• the units for _________ energy are kg*m2/s2 which is also called joules, J
Potential Energy
Def: _________ _________is stored energy as a result of _________ or _________
• potential energy is energy with the potential to do work
• Two forms of potential energy are _____________ potential energy and _____________
potential energy
• Def: ___________ potential energy is potential energy that depends upon an object’s ___________
• Gravitational potential energy _____________ when an object is at a higher _____________
• An object’s gravitational potential energy depends on its _________, _____________ &
_____________ due to _____________
• The formula for gravitational potential energy = mgh where m= mass (kg), g= 9.8 m/s2 (the free
fall acceleration of gravity) & h = height in meters, m
• When you ___________all the units together you get kg*9.8m/s2*m or kg*m2/s2 which is ________
• Def: _____________ potential energy is the potential energy of an object that is
_____________ or _____________
• An object is elastic if it springs back after being stretched
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Practice Problems – YES!!! I want you to try them!!!
• Calculate the kinetic energy of a 1500kg car moving at 29m/s.
• A bowling ball traveling at 2.0m/s has 16J of kinetic energy. What is the mass of the bowling
ball in kg?
• Calculate the potential energy of a car with a mass of 1200kg at the top of a 42m hill.
• Calculate the potential energy of a 55g egg held out of a 2nd story window, 6m off the ground.
Forms of Energy
• The major forms of energy are _________________ energy, _________________energy,
_________________ energy, _________________ energy, _________________energy and
_________________energy
• Def: _________________ energy is the energy associated with the _________________and
_________________ of everyday objects
• Def: _________________energy is the total potential energy and kinetic energy of all the
microscopic particles in an object
• Def: _________________energy is the energy stored in chemical bonds
• Def: _________________ energy is the energy associated with electric charges
• Def: _____________energy is a form of energy that travels through space in the form of _________
• Def: ______________ energy is the energy stored in ______ ___________
15.2 Energy Conversion & Conservation
Objectives: 1. Describe how energy can be converted from one form to another 2. Explain the law of conservation of energy 3. Discuss the energy conversion that takes place as an object falls toward Earth 4. Discuss how energy and mass are related
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Energy Can be Converted from One Form to Another
• Def: energy_________________is the process of changing energy from ______ form to another
• Sometimes energy is converted to other forms in a _________ of __________
• Ex: striking a match uses chemical energy from your ______________, then
_________________ between match and box converts _________________ energy to
_________________ energy, _________________ energy triggers a chemical reaction
releasing more _________________energy
• Often energy converts _________________ from one form to another
• a wind up toy, for example, is _________________ energy to kinetic energy
Conservation of Energy + Energy Conversions and Gravity
• The Law of _________________ of ___________ states that energy cannot be
_____________or _________________
• The_________________ potential energy of an object is _________________ to the kinetic
energy of motion as an object _________
• _________________ constantly convert _________________l energy to
_________________energy and _________________energy to_________________energy as
the pendulum_________________
• At the_______________ of the swing, the pendulum has _________________ kinetic energy
and _____________ potential energy
• On either side, the pendulum will have a _________________ of _________________ energy
+ _________________ energy
• Q: Where is the potential energy the greatest and kinetic energy zero?
Energy and Mass
• _________________energy = _________________ energy + _________________energy
• _________________ energy is also _________________
• (kinetic energy + potential energy) beginning = (kinetic energy + potential energy) end
• _________________ has an equation: _________________ (this is a really FAMOUS equation)
where E is energy (J), m is mass (kg) & c2 is the speed of light squared (3 x 108 m/s)2
• This equation says that ____________ and ____________are _________________ and can be
_________________ into each other
• It also means that a tiny amount of ____________ can produce enormous
_________________of _____________
• Mass and energy together are always _________________
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Energy Resources Objectives:
1. Give examples of the major nonrenewable and renewable energy sources
2. Explain how energy resources can be conserved
Nonrenewable and Renewable
• ___________ energy resources include ______, _______ _______, ______and ____________
• Oil, natural gas and coal are _________ ________
• _________ ________were formed _________________ from once _____________organisms
• Most nonrenewable resources are considered _________________, _________________ and
are known to cause_________________
• _________________energy resources include _________________, ______________,
_________________, wind, and __________________
• Def: __________________ energy is energy obtained from flowing _____________
• Hydroelectric energy production usually involves the building of a _________
• Hydroelectric is available, used today and generally __________________
• Def: __________energy is __________________converted to __________________energy
• ___________ energy is __________________ and its use is__________________until
technology improves
• Def: __________________energy is__________________energy beneath the earth’s surface
• It is __________________and available in many areas due to naturally occurring hot springs
• ___________ places are not near a volcano or hot springs
• Def: ______________energy is the energy stored in ___________ _______
• __________________ can be converted directly to__________________energy
• __________________waste such as turning corn into ________________for auto fuel is an ex
• This technology is_________________________
• _____________ energy requires a lot of___________ and a place that has a lot of _______
(ummm….anyone remember from Biology where this would be??)
• It is __________________ and not ________________ at this time although research continues
• __________________ fuel cells are being used in some places to generate
__________________by reacting hydrogen with oxygen (umm…remember the movie?)
• The main source of hydrogen is __________________
• This technology is __________________and __________________ to be a research and
development project for future energy sources
Conservation of Resources
• Energy resources can be conserved by __________________ energy needs and by
__________________ the efficiency of energy use
• Def: __________________ __________________ is finding ways to use ________energy or
use energy more __________________
• Q: Can you think of some ways we can conserve energy resources?
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Mechanical Waves and Sound
17.1 Mechanical Waves Objectives: 1. Explain what causes mechanical waves 2. Name and describe the three main types of mechanical waves
How do we know that light and sound are waves? → Interference
What Causes Mechanical Waves Def: A wave is a disturbance that carries energy through space or matter by causing oscillations in the medium Def: What a wave travels through is the medium (sound-air, earthquake-ground) • Medium: is a material (matter) that mechanical waves travel through solid liquid or gas.
– Ex. Air, water, aluminum, copper, • The speed of mechanical waves changes with different mediums Def: Waves that require a medium to travel are called mechanical waves • Mechanical waves carry energy from one place to another by using matter (a medium) • A wave will travel as long as it has energy. • Mechanical waves require matter to travel • Mechanical wave is created when a source of energy causes a vibration to travel
through a medium • Vibration: a repeating motion that follows a pattern • Sound is created by vibrations
– Vocal cords are an example
3 types of mechanical waves • There are 3 types of mechanical waves
– Transverse waves – Longitudinal waves/ Compressional – Surface waves
Types of Mechanical Waves
• The three main types of mechanical waves are transverse waves, longitudinal waves and surface waves
• Particles in a medium can vibrate up and down or back and forth as a wave moves by Def: If the particles move up and down they will move perpendicular to the direction of the wave-called a transverse wave
Transverse Waves • Transverse waves: is a wave that causes the medium to vibrate at right angles
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(perpendicular) to the direction in which the wave travels • Up & Down, or Side to Side motion • Draw a picture of a transverse wave • Ex.
– Water – Rope – Slinky – Electromagnetic (radio waves, infrared, etc)
• Transverse waves take the shape of sine curves (looks like an s on its side) • Crest: is the highest point above the resting position (top of the wave) • Trough: is the lowest point below the resting position (bottom of the wave) • Resting position: is the flat position of a wave before it starts moving
– Slinky demo • Def: Difference between high and low is called amplitude • Bigger amplitudes mean more energy
Transverse Wave • Transverse Waves
– medium moves perpendicular to the direction of wave motion
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Wave Anatomy Def: in a longitudinal wave the medium moves in the same direction as the wave Def: In longitudinal waves the bunched area is a compression (think of a slinky) Def: The spaced out areas are called rarefactions Def: Amplitude on a longitudinal wave is maximum deviation from normal density or pressure • At the boundary between two mediums (on the ocean for example) surface waves
develop Def: Surface waves are combinations of both types of waves • The particles in the medium of a surface wave move back and forth and up and down
resulting in a circle, but they end up where they started
Longitudinal Waves
• Longitudinal Waves (a.k.a. compressional) – medium moves in the same direction as wave motion
• Wave Anatomy
Surface Wave
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• Surface wave: is a wave that has characteristics of both transverse and longitudinal waves
• Up & down movement like a transverse • Parallel movement of energy like longitudinal • Ex.
– Ocean Waves – Earthquakes (waves through Earth’s surface)
17.2 Properties of Mechanical Waves • Objectives: • 1. Explain what determines the frequency of a wave • 2. Solve problems for frequency, wavelength and speed • 3. Describe how amplitude and energy are related
Frequency Def: periodic motion is any motion that repeats at regular time intervals Def: Frequency is how many waves pass by in a given time • Frequency = 1/period = 1 / T = f • It is measure in hertz (Hz) which is 1/s where s is seconds • Humans can hear 20Hz to 20000Hz https://www.youtube.com/watch?v=h5l4Rt4Ol7M • A wave’s frequency equals the frequency of the vibrating source producing the wave
Problems involving f, λ (wavelength) & speed • Def: Wavelengths of waves are measured from one crest to the next (crest to crest OR
trough to trough) or from one compression to the next • It is represented by the Greek letter lambda whose symbol is λ • The period of a wave is how long it takes for a complete wave to go by a spot, symbol is
T • Increasing the frequency (f) of a wave decreases the wavelength (λ)
Wavelength • Wavelength: is the distance of a complete cycle (either crest to crest or trough to trough) • Long wavelength = low frequency • Short wavelength = high frequency • Recall that speed = distance / time • For waves we can use wavelength
for distance (in meters, m) and period for time (s for seconds)
• Speed = wavelength X frequency v = λ * f • The speed of a wave depends on
what it travels through (medium) • If the medium particles are closer
together the energy from the wave can make vibrations easier
• So waves travels best in solids, then liquids, and worse in air
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Measuring Waves • Frequency ( f )
– # of waves passing a point in 1 second – Hertz (Hz)
Measuring Waves • Velocity ( v )
– speed of a wave as it moves forward – depends on wave type and medium
Measuring Waves
• EX: Find the velocity of a wave in a wave pool if its wavelength is 3.2 m and its frequency is 0.60 Hz.
• EX: An earthquake produces a wave that has a wavelength of 417 m and travels at 5000 m/s. What is its frequency?
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Wave Speed • Wave Speed = wavelength X frequency • Wave speed changes in different mediums • If waves are traveling the same speed, then wavelength and frequency are
INDIRECTLY related
Amplitude and Energy • Def: amplitude is the difference between crest and the rest position or point of origin • Def: the rest position or point of origin is an imaginary line through the middle of the
wave that separates the crest from the trough • The more energy a wave has, the greater its amplitude
Amplitude • Amplitude: is the distance from the resting position to either a crest or trough • Energy and amplitude are DIRECTLY related • High energy = high amplitude • Low energy = low amplitude • Amplitude in sound is called volume • Light waves travel faster than sound • Sound waves travel faster in liquids and solids than gas • Light waves travel faster in gases and vacuums than in liquids and solids. • Bill Nye the Science Guy S01E12 Sound • https://www.youtube.com/watch?v=A79r26c3CE8
Behavior of Waves Objectives: 1. Explain reflection and refraction and how they affect waves 2. Identify several factors that affect the amount of wave diffraction 3. Discuss two types of interference 4. Explain what a standing wave is and detail the wavelengths that produce it
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Reflection
• Def: Reflection occurs when a wave meets a boundary and bounces off • Reflection does not change the speed or frequency of a wave, but the wave can be
flipped upside down Ex. Mirror Behavior of Waves
• Reflection: is when a wave bounces off a surface it can not pass through • Reflection does not change the speed or frequency (the wave can be flipped upside
down or side to side) Ex. Mirror • Law of Reflection: the angle of incidence (incoming wave) = the angle of reflection
(outgoing wave) • All waves can be reflected • The reflection of sound is called an echo
Refraction • Def: Refraction is the bending of a wave as it travels through different mediums • When a wave enters a medium at an angle, refraction occurs because one side of the
wave moves more slowly than the other side
Examples of Refraction • Refraction: is the bending of a wave as it enters a new medium • Ex. light waves
– Ruler in a beaker of water • Ex. sound waves
– Listening to sound underwater
Different colors refract different amounts Refraction caused by difference in wave speed between left and right C = λ f •F stays constant •C slows down • λ gets smaller
Diffraction • Def: Diffraction is the bending of a wave around an obstacle • A wave diffracts more if its wavelength is large compared to the size of an opening or
obstacle
Diffraction • Diffraction: is the bending of a wave as is moves around an obstacle or passes through
a narrow opening • Page 510 • Eddy: is an area behind a mid-stream boulder where the water flows in a reverse
direction (provides safety for rafters) • Chute: is an area of a river where the water is constricted to a narrow passage
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Diffraction • A wave diffracts more if its wavelength is large compared to the size of an opening or
obstacle • Sound has a bigger λ, diffracts more
Interference • The two types of interference are constructive interference and destructive interference • The combo of two or more waves at the same place at the same time causes
interference • Def: When two crests meet the interference is constructive-the wave becomes more
energetic-the amplitude increases • Def: When a crest and a trough meet they cancel each other and decrease the
amplitude –destructive
Constructive Interference • Constructive Interference: is when 2 or more waves combine to form a wave with a
larger displacement (amplitude) Destructive interference:
• Destructive interference: is when 2 or more waves combine to form a wave with a smaller displacement (amplitude) add together
Standing Waves • Standing wave: is wave or waves that appear to stay in the same place • Plucking a guitar string • Waves in a river • Node: is the point on a standing wave where there is no displacement (amplitude) • Antinodes: are the crests and the troughs on a standing wave • Interference may cause standing waves- • Def: Standing waves appear not to move along the medium, caused by interference
between the incoming and reflected wave • Has areas of destructive interference where there is no vibration called nodes • Def: a node is a point on a standing wave that has no displacement from the rest
position • Areas of maximum interference called antinodes • Def: an antinode is a point where a crest & trough meet midway between 2 nodes
Standing waves
• iphone 4 inside a guitar oscillation! • https://www.youtube.com/watch?v=INqfM1kdfUc • A standing wave forms only if half a wavelength or
a multiple of half a wavelength fits exactly into the length of a vibrating cord
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Sound and Hearing
Objectives: 1. Describe the properties of sound waves and explain how sound is produced and reproduced 2. Describe how sound waves behave in applications such as ultrasound and music 3. Explain how relative motion determines the frequency of sound as the observer hears
Sound Waves • Sound waves are longitudinal waves • The speed of sound changes due to different types of mediums • Chart 514 • Speed: is the distance traveled in a certain amount of time • Meters/second: m/s
Properties of Sound Waves • Sound waves are longitudinal waves • They have compressions are rarefactions • Behaviors can be explained by the properties of speed, intensity, loudness, frequency
and pitch Sound Waves
• Intensity: depends on the amplitude (volume) and the distance from the source • Decibels: (dB) is the unit for sound intensity • Chart on 515 • Damage to ears around 120 dB • Frequency: is the number of wave cycles to pass a given point in one second • Measured in hertz (Hz) • Pitch: is the perceived frequency of sound • Different notes in music • All the different notes have a unique frequency • Ultrasound: use sound to locate objects or create pictures • SONAR, fish finders, radar • Animals use “echo-location” • Bats, dolphins, whales • Pregnant ladies get ultra sounds to check the baby’s health
How Sound Waves Behave & Relative Motion • Ultrasound is used in a variety of applications, including sonar and ultrasound imaging • Def: Sonar is a technique for determining the distance to an object under water
Sound Waves
• Doppler Effect: pitch changes due to the object creating the sound moving closer or farther away
Doppler’s Effect • Higher pitch means faster frequency • As the source of the waves moves it changes the frequency (this is the Doppler Effect) • As it moves toward you the pitch rises and away from you the pitch lowers = Doppler
Effect
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Human Ear • Outer ear: the collect and funnel the sound waves into the middle ear • Middle ear: amplifies the vibrations • Inner ear: are where nerve endings receive and send the signal to the brain • The brain interprets those signals as sound • For us to hear, the outer ear gathers & focuses sound into the middle ear where the
vibrations are received and amplified • The inner ear uses nerve endings to sense vibrations and send signals to the brain • http://ed.ted.com/on/6yWWWNcR • Resonance: waves of the same frequency combine (constructive interference) • amplifies the sound • Resonance can also cause to vibrate • Every object has a natural frequency, if a sound wave with the same frequency hits it, it
will cause the object to vibrate • Def: intensity is the rate at which a wave’s energy flow through a given area • The decibel (dB) compares the intensity of different sounds • Def: loudness is a physical response to the intensity of sound modified by physical
factors • As intensity increases, loudness increases • Loudness also depends on the health of your ears and how your brain interpret sounds • Def: pitch is the frequency of a sound as you perceive it • Sound is recorded by converting sound waves into electronic signals that can be
processed and stored • Sound is reproduced by converting electronic signals back to sound waves • Most musical instruments vary pitch by changing the frequency of standing waves
Seismic waves
• Seismic waves are the waves of energy caused by the sudden breaking of rock within the earth or an explosion. They are the energy that travels through the earth and is recorded on seismographs.
• http://science.howstuffworks.com/nature/natural-disasters/earthquake4.htm
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Mechanical Waves and Sound
17.1 Mechanical Waves
Objectives:
1. Explain what causes mechanical waves
2. Name and describe the three main types of mechanical waves
How do we know that light and sound are waves?
→ Interference
What Causes Mechanical Waves
Def: A _________ is a disturbance that carries energy through space or matter by causing
___________________ in the _________
Def: What a _________ travels through is the _________ (sound-air, earthquake-ground)
• __________: is a material (_________) that mechanical _________travel through -
_________, _________ or _________.
– Ex. _________, _________, ______________, _________
• The _________ of mechanical waves _________ with different _________
Def: _________ that require a _________to travel are called _____________ _________
• Mechanical waves carry _________ from _________place to another by using _________
(a _________)
• A _________will travel as long as it has _________.
• ______________ waves require _________ to travel
• A Mechanical wave is created when a source of _________ causes a ____________ to
_________ through a _________
• _______________: a _____________ motion that follows a _________
• _________is created by ____________
– _________ _________are an example.
3 types of mechanical waves
• There are 3 types of mechanical waves
– _________ _________
– ___________________ _________/ __________________
– _________ _________
Longitudinal Transverse
Name __________________________Date __________ Block ______ 143
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Types of Mechanical Waves
• The three main types of mechanical waves are _________ _________,
__________________ __________and _________ _________
• Particles in a _______________ can vibrate _____ and _______ or _______ and _______
as a wave moves _____
Def: If the particles move ____ and ______ they will move _______________________ to the
direction of the wave-called a _________ _________
Transverse Waves
• _________ _________: a wave that causes the medium to _________ at _________
_________ (perpendicular) to the direction in which the wave_________
• _________ and _________, or _________ to _________ motion
• Ex.
– _________
– _________
– _________
– __________________ (radio waves, infrared, etc)
• _____________ waves take the shape of_________ curves (looks like an ___on its side)
• _________: is the _________ point above the _________ position (top of the wave)
• _________: is the _________point below the _________ position (bottom of the wave)
– _________ _________: is the _________ position of a wave before it starts
_________
– Slinky demo
• Def: Difference between high and low is called ____________
• Bigger ________________ mean more _________
Transverse Wave
• _______________ ____________
– _________ moves perpendicular to the
direction of _________ _________
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Transverse Waves
• Wave Anatomy
• Def: in a _______________ wave the medium moves in the ______direction as the _____
• Def: In longitudinal waves the __________ area is a ________________ (think of a slinky)
• Def: The spaced out areas are called ______________________
• Def: _________________ on a _________________wave is maximum
_________________ from normal density or pressure
• At the _________________between two ____________(on the ocean for example)
______________ ___________ develop
• Def: _________ ________are combinations of _______ types of waves
• The particles in the medium of a surface wave move ______ and ______ AND ____ and
________ resulting in a circle, but they ______ ____ where they ___________
Longitudinal Waves
• Longitudinal Waves (a.k.a. compressional)
– _________ moves in the same direction as _______ _______
• Wave Anatomy
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Surface Wave
• __________ ______________: is a wave that has characteristics of both _____________
and ________________ waves
• ____ & _____ movement like a _________________
• _________________ movement of energy like _________________
• Ex.
– ________ _________
– _________________ (waves through Earth’s surface)
17.2 Properties of Mechanical Waves
Objectives:
1. Explain what determines the frequency of a wave
2. Solve problems for frequency, wavelength and speed
3. Describe how amplitude and energy are related
Frequency
Def: ____________ motion is any motion that ____________at regular time intervals
Def: _________________ is how many waves pass by in a given time
• Frequency = 1/period = 1 / T = f
• It is measure in __________ (____) which is 1/s where s is seconds
• Humans can hear ____Hz to _________Hz
https://www.youtube.com/watch?v=h5l4Rt4Ol7M
• A wave’s frequency equals the frequency of the ____________ ______ producing the
wave
Problems involving f, λ (wavelength) & speed
• Def:________________________ of waves are measured from one _______ to the next
________ (crest to crest OR trough to trough) or from one _________________ to the next
_________________
• It is represented by the Greek letter _________ whose symbol is λ
• The ________of a wave is how ______ it takes for a complete wave to go by a ________,
symbol is T
• Increasing the _______________ (f) of a wave __________ the _________________ (λ)
Wavelength
• __________________: is the distance
of a _____________ _______ (either
crest to crest or trough to trough)
• _______ wavelength = _______
frequency
• _______ wavelength = _______
frequency
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• Recall that ___________ = __________ / __________
• For waves we can use ______________ for distance (in _______, m) and _______ for time
(s for seconds)
• __________ = ________________ X _______________
v = λ * f
• The ________ of a wave depends on what it ____________ through (__________)
• If the __________ particles are closer together the __________ from the wave can make
________________ easier
• So waves travels best in __________, then __________, and worse in __________
Measuring Waves
• Frequency ( f )
– # of waves passing a point in 1 second
– Hertz (Hz)
– shorter wavelength = higher frequency = higher energy
Measuring Waves
• Velocity ( v )
– speed of a wave as it moves forward
– depends on wave type and medium
– V: velocity (m/s)
– λ: wavelength (m)
– ƒ: frequency (Hz)
v = wave λ × f
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Measuring Waves
• EX: Find the velocity of a wave in a wave pool if its wavelength is 3.2 m and its frequency
is 0.60 Hz.
Measuring Waves
• EX: An earthquake produces a wave that has a wavelength of 417 m and travels at 5000
m/s. What is its frequency?
Wave Speed
• _________ ___________ = _____________ X _____________
• Wave speed ____________ in different _____________
• If waves are traveling the ________ speed, then _____________ and _____________ are
__________________ related
Amplitude and Energy
• Def: _____________ is the _____________ between _____________and the _______
position OR point of _____________
• Def: the _______ position or point of _________ is an imaginary line through the
_________of the ______ that separates the _______ from the _______
• The more ______________ a wave has, the greater its ________________
Amplitude
• _________________: is the ___________ from the ___________ position to either a
________or___________
• ________ and ___________ are ___________related!
• ______ energy = ______ amplitude
• ______ energy = ______ amplitude
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• _____________________ in sound is called _____________
• ______ waves travel faster than ______
• _________ waves travel faster in __________ and _________than ______
• ______ waves travel faster in ______ and __________ than in ______ and ______.
17.3 Behavior of Waves
Objectives:
1. Explain reflection and refraction and how they affect waves
2. Identify several factors that affect the amount of wave diffraction
3. Discuss two types of interference
4. Explain what a standing wave is and detail the wavelengths that produce it
Reflection
• Def: ________________ occurs when a wave meets a ________________ and
______________ off
• ________________ does _____ change the ________ or frequency of a wave, but the
wave can be _______________ _____________down Ex. Mirror
Behavior of Waves
• ________________: is when a wave __________ off a surface it can _____ pass through
• Reflection does not change the speed or _________________ (the wave can be flipped
upside down or ______ to ______) Ex. Mirror
• ______ ______ ____________: the angle of ___________(incoming wave) = the angle of
______________ (outgoing wave)
• All waves can be _____________
• The reflection of sound is called an ______
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Reflection
Refraction
• Def: _________________ is the ___________of a wave as it travels through different
_______________
• When a ____________ enters a ______________ at an ___________, refraction occurs
because one side of the wave moves more _____________than the other side
Examples of Refraction
• _________________: is the bending of a wave as it enters a new medium
• Ex. ___________waves
– Ruler in a beaker of water
• Ex. ___________ waves
– Listening to sound underwater
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Different colors refract different amounts
C = λ f
•F stays ______
•C ______ down
• λ gets _______
_____________________ caused by difference in wave speed between left and right
Diffraction
• Def: __________________ is the _________ of a wave ________ an obstacle
• A wave __________ more if its __________________ is large compared to the size of an
_________ or _______________
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Diffraction
• ________________: is the bending of a wave as is moves around an ___________ or
passes through a ___________opening
• Page 510
• _________: is an area behind a mid-stream __________ where the water flows in a reverse
direction (provides safety for ___________)
• _________: is an area of a river where the water is _______________to a narrow passage
Diffraction
• A wave diffracts more if its wavelength is large compared to the size of an opening or
obstacle
• Sound has a bigger _________________ (λ), diffracts __________
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Interference
• The two types of interference are _______________ interference and
_________________interference
• The combo of ____ or more waves at the same place at the same time causes ____________
• Def: When _____ crests meet the ________________ is constructive-the wave becomes
more ________________ -the amplitude__________________
• Def: When a ________ and a ____________ meet they cancel each other and
______________ the ________________ – _______________
Constructive Interference
• ______________ _____________: is when _____ or more waves ___________ to form a
wave with a larger _________________ (___________________)
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Destructive interference:
• ______________ _____________: is when ______ or more waves __________ to form a
wave with a _____________displacement (amplitude) _______together
Standing Waves
• ____________ _________: is a wave or waves that appear to stay in the _______ place
• Plucking a guitar ________
• Waves in a _________
• _________: is the _________ on a _________wave where there is ___ displacement
(amplitude)
• _________: are the _________ and the _________ on a _________ wave
• ___________________ may cause standing waves
• Def: _____________ waves appear _____ to move along the ___________, caused by
interference between the ______________ and ______________ wave
• Has areas of ________________ interference where there is ___ vibration called ______
• Def: a ______ is a point on a standing wave that has ___ displacement from the _______
position
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• Areas of maximum interference called _______________
• Def: an_______________ is a point where a _______ & _______ meet ________ between
______ nodes
• A ______________ wave forms only if ________ a wavelength or a ______________ of
half a wavelength fits______________ into the length of a __________ cord
Sound and Hearing
Objectives:
1. Describe the properties of sound waves and explain how sound is produced and reproduced
2. Describe how sound waves behave in applications such as ultrasound and music
3. Explain how relative motion determines the frequency of sound as the observer hears
Sound Waves
• Sound waves are___________________ waves
• The ________ of _________ changes due to different types of _____________
• Chart 514
• _______________: is the distance traveled in a certain amount of time
• _______________: m/s
Properties of Sound Waves
• Sound waves are _______________ waves
• They have _______________ are _______________
• Behaviors can be explained by the properties of _______________, _______________,
_______________, _______________ and _______________
Sound Waves
• _______________: depends on the amplitude (____________) and the distance from the
source
• _______________: (dB) is the unit for sound intensity
• Chart on 515
• Damage to ears around _______ dB
• _______________: is the number of wave cycles to pass a given point in one second
____________
____________
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14
• Measured in _______________ (Hz)
• __________: is the perceived frequency of sound
• Different ___________in music
• All the different ___________ have a unique _______________
• _______________: use sound to locate _________ or create ___________
• _______________, _______ ________, _
• Animals use “_______-location”
• _______ , _____________, _____________
• Pregnant ladies get ultra sounds to check the baby’s ____________
How Sound Waves Behave & Relative Motion
• ________________ is used in a variety of applications, including sonar and ultrasound ____________
• Def: _________is a technique for determining the distance to an object under ________
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15
Sound Waves
• Doppler Effect: pitch changes due to the object creating the sound moving closer or farther
away
Doppler’s Effect
• Higher pitch means faster frequency
• As the source of the waves moves it changes the frequency (this is the Doppler Effect)
• As it moves toward you the pitch rises and away from you the pitch lowers = Doppler
Effect
• _________ ____________: ___________changes due to the object creating the sound
moving____________ or________________ away
Doppler’s Effect
• _________ pitch means _________ frequency
• As the _________ of the _________ moves it changes the _____________ (this is the
______________ Effect)
• As it moves _________ you the pitch ______ and _______from you the pitch _________ =
Doppler Effect
Human Ear
• ________ ____: collects and __________the ________ waves into the ______ ear
• ________ ____: amplifies the _____________
• ________ ____: are where nerve endings ____________ and _______ the signal to the
__________
• The brain interprets those __________ as _________
• For us to hear, the____________ ear _________ & _________sound into the_________ear
where the _________ are _________ and _________
• The_________ ear uses nerve endings to_________ vibrations and send _________ to the
_________
• _____________: waves of the same frequency _________ (_____________ interference)
• _________ the _________
• _______________can also cause to _________
• Every object has a _________frequency, if a sound wave with the same frequency hits it, it
will cause the object to _________
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• Def: _______________ is the_______ at which a wave’s __________ flow through a given area
• The ____________ (dB) compares the ____________ of different sounds
• Def: _____________ is a physical response to the ____________ of sound
______________ by physical factors
• As intensity_________, loudness _________
• _________also depends on the _________ of your ears and how your brain _________
sounds
• Def: _________ is the frequency of a sound as you perceive it
• _________ is recorded by converting sound waves into _____________ _________that
can be processed and stored
• _________ is _____________ by converting ____________ signals _________ to sound waves
• Most ______________ instruments vary _________ by changing the frequency of standing
waves
Seismic waves
• ______________waves are the waves of _____________ caused by the sudden
_______________ of rock within the earth or an ______________. They are the energy
that travels through the earth and is recorded on _____________________.
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Name:_______________________________________________ Date:_________________ Physical Science Block:_____________
Wave Calculations
Speed of a wave = wavelength x
frequency
v = λxf
v = velocity (speed), measured in
meters/second (m/s) λ = wavelength, measured in meters (m)
f = frequency, measured in Hertz (Hz)
The frequency of a wave is the number
of complete was passing a point in a
given time.
f = v/λ f = frequency, measured in Hertz (Hz) v = velocity (speed), measured in
meters/second (m/s)
λ = wavelength measures in meter
The wavelength is the length of a
single wave and the unit is a meter.
λ = v/f λ = wavelength measures in meter v = velocity (speed), measured in meters/second (m/s)
f = frequency, measured in Hertz
(Hz)
1. A wave along a guitar string has a frequency of 540 Hz and a wavelength of 2.5 meters. Calculate the speed of the wave.
Given Equation Substitution Final Answer
2. The speed of sound in air is about 340 m/s. What is the wavelength of sound waves produced by a guitar string vibrating at
490 Hz?
Given Equation Substitution Final Answer
3. The speed of light is 300,000,000 m/s. What is the frequency of microwaves with a wavelength of 0.01 meter?
Given Equation Substitution Final Answer
4. What is the velocity of a wave with a frequency of 760 Hz and a wavelength of 0.35m?
Given Equation Substitution Final Answer
5. The string on a piano that produces an A sharp vibrates with a frequency of 235 Hz. If the sound waves produced by this
string have a wavelength (in air) of 1.49 meters, what is the speed of sound in air?
Given Equation Substitution Final Answer
6. The average wavelength in a series of ocean waves is 15.0 meters. A wave crest arrives at the shore an average of every 10.0
seconds, so the frequency is 0.100 Hz. What is the average speed of the waves?
Given Equation Substitution Final Answer
7. An FM radio station broadcasts electromagnetic waves at a frequency of 94.5 MHz (equal to 94,500,000 Hz). These radio
waves have a wavelength of 3.17 meters. What is the speed of the waves?
Given Equation Substitution Final Answer
159
8. Green light has a wavelength of 0.00000052 meters. The speed of light is 300,000,000 m/s. Calculate the frequency of green
light waves with this wavelength.
Given Equation Substitution Final Answer
9. What is the frequency of a pendulum that is moving at 30 m/s with a wavelength of 0.35 m?
Given Equation Substitution Final Answer
10. What is the wavelength of a sound wave with a frequency of 220 Hz if its speed is 340 m/s?
Given Equation Substitution Final Answer
11. What is the wavelength of a sound wave moving at 340 m/s with a frequency of 256 Hz?
Given Equation Substitution Final Answer
12. A wave with a frequency of 14 Hz has a wavelength of 3 meters. At what speed will this wave travel?
Given Equation Substitution Final Answer
13. The speed of a wave is 65 m/s. If the wavelength is 0.8 m, what is the frequency of the wave?
Given Equation Substitution Final Answer
14. The note A above middle C on a piano emits a sound wave with a wavelength of 0.77 meters. What is the frequency of the
wave? Use 340 m/s as the speed of the sound wave.
Given Equation Substitution Final Answer
15. A wave has a frequency of 46 Hz and a wavelength of 1.7 meters, What is the speed of this wave?
Given Equation Substitution Final Answer
16. A wave travelling at 230 m/s has a wavelength of 2.1 m. What is the frequency of this wave?
Given Equation Substitution Final Answer
160
17. A wave with a frequency of 500 Hz is travelling at a speed of 340 m/s. What is its wavelength?
Given Equation Substitution Final Answer
18. A wave has a frequency of 540Hz and is travelling at 340 m/s. What is its wavelength?
Given Equation Substitution Final Answer
19. A wave has a wavelength of 125 meters and is moving at a speed of 20 m/s. What is the frequency?
Given Equation Substitution Final Answer
20. A wave has a frequency of 900 Hz and a wavelength of 200 m. At what speed is this wave travelling?
Given Equation Substitution Final Answer
21. A wave has a wavelength of 0.5 meters and a frequency of 120 Hz, what is the waves speed?
Given Equation Substitution Final Answer
22. A wave with a frequency of 14 Hz has a wavelength of 3 meters, At what speed will this wave travel?
Given Equation Substitution Final Answer
23. If a wave has a frequency of 27 Hz and has a wavelength of 150 m, what is it speed?
Given Equation Substitution Final Answer
24. If wave has a frequency of 27 Hz and is travelling at a speed of 46 m/s, what is the wavelength of the wave?
Given Equation Substitution Final Answer
25. If a wave has a wavelength of 502 m and is traveling at a speed of 100 m/s, what is its frequency?
Given Equation Substitution Final Answer
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26. If a wave has a wavelength of 326 m and is traveling at a speed of 14 m/s, what is the frequency of the wave?
Given Equation Substitution Final Answer
27. If a wave has a frequency of 97 Hz and a wavelength of 1378 m. what speed is it travelling?
Given Equation Substitution Final Answer
28. If a wave has a frequency of 78 Hz and has a wavelength of 1378 m, what is the wave’s speed?
Given Equation Substitution Final Answer
29. What is the speed if the wavelength is 8 m and the frequency is 20 Hz?
Given Equation Substitution Final Answer
30. What is the wavelength if the speed is 50 m/s and the frequency is 25 Hz?
Given Equation Substitution Final Answer
31. What is the frequency if the speed is 120 m/s and the wavelength is 3 m?
Given Equation Substitution Final Answer
32. What is the wavelength if the speed is 345 m/s and the frequency is 790 Hz?
Given Equation Substitution Final Answer
33. What is the frequency if the speed is 345 m/s and the wavelength is .25 m?
Given Equation Substitution Final Answer
34. What is the speed of a water wave with a frequency of 0.35 Hz and a wavelength of 7 meters?
Given Equation Substitution Final Answer
35. Sound waves in air travel at approximately 333 m/s. Calculate the frequency of a 2.5 m long sound wave
Given Equation Substitution Final Answer
162
Name _____________________________
Answer sheet for Waves Worksheet
Choose the correct answer choice and mark it on your answer sheet. IF you don’t see the correct answer, rework
it to make sure you did it right!
________1. A. 0.004 B. 216 C. 1350
________2. A. 144 B. 0.7 C. 166600
________3. A. 3.0 x 1111 B. 3.0 x 1010 C. 3.0 x 106
________4. A. 4.6 x 104 B. 2171 C. 266
________5. A. 0.0063 B. 158 C. 350.15
________6. A. 1.5 B. 150 C. 0.0067
________7. A. 2.9 x 107 B. 3.0 x 108 C. 3.35 x 10-8
________8. A. 1.73 x 10-11 B. 5.77 x 1014 C. 15.6
________9. A. 85.71 B. 10.5 C. 0.012
________10. A. 0.65 B. 1.5 C. 74800
________11. A. 87040 B. 0.75 C. 1.33
________12. A. 0.214 B. 4.67 C. 42
________13. A. 81.25 B. 52 C. 0.0123
________14. A. 0.00226 B. 442 C. 261.8
________15. A. 78.2 B. 0.037 C. 27
________16. A. 0.009 B. 109.5 C. 483
________17. A. 0.68 B. 170,000 C. 1.47
________18. A. 0.63 B. 1.59 C. 183,600
________19. A. 2500 B. 6.25 C. 0.16
________20. A. 0.22 B. 4.5 C. 180,000
________21. A. 0.0042 B. 240 C. 60
________22. A. 0.0214 B. 4.67 C. 42
________23. A. 4050 B. 5.6 C. 0.18
________24. A. 0.59 B. 1.70 C. 1242
________25. A. 0.199 B. 502 C. 50200
________26. A. 0.043 B. 4564 C. 23.3
________27. A. 14.21 B. 0.07 C. 133,666
________28. A. 0.057 B. 17.67 C. 107,484
________29. A. 160 B. 2.5 C. 0.4
________30. A. 0.5 B. 2 C. 1250
________31. A. 360 B. 40 C. 0.25
________32. A. 0.44 B. 2.29 C. 272,550
________33. A. 7.2 x 10-4 B. 1380 C. 86.25
________34. A. 0.05 B. 20 C. 2.45
________35. A. 0.0075 B. 133.2 C. 832.5
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