Name: ____________________________________ Period: _______ Date: _________ ID: A

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PHYSICS First Half of the Year Review

Multiple Choice.

1. Which of the following line segments on a velocity versus time graph is physically impossible?a.  straight line with positive slope b.  straight line with negative slope c.  vertical line d.  horizontal line

2. A child with a mass of 23 kg rides a bike with a mass of 5.5 kg at a velocity of 4.5 m/s to the south. Compare the momentum of the child with the momentum of the bike.a.  The child has a greater momentum than the bike. b.  Both the child and the bike have the same momentum. c.  Neither the child nor the bike has momentum. d.  The bike has a greater momentum than the child.

3. Suppose you are given a position versus time graph. The slope of a line drawn tangent to a point on the curve of this graph describes what quantity?a.  displacement b.  average velocity c.  acceleration d.  instantaneous velocity

4. How much elastic potential energy is stored in a bungee cord with a spring constant of 10.0 N/m when the cord is stretched 2.00 m?a.  20.0 J b.  10.0 J c.  40.0 J d.  200 J

5. A rubber ball moving at a speed of 5 m/s hit a flat wall and returned to the thrower at 5 m/s. The magnitude of the momentum of the rubber balla.  increased. b.  decreased. c.  remained the same. d.  was not conserved.

6. The SI base unit used to measure mass is thea.  Newton. b.  kilogram. c.  pound. d.  gram.

7. What are the units of the coefficient of friction?a.  N2 b.  1/N c.  The coefficient of friction has no units. d.  N

8. Two balls of dough collide and stick together. Identify the type of collision.a.  perfectly inelastic b.  elastic c.  inelastic d.  nearly elastic

9. The magnitude of the gravitational force acting on an object isa.  frictional force. b.  inertia. c.  mass. d.  weight.

10. If you know the acceleration of a car, its initial velocity, and the time interval, which of the following can you predict?a.  the magnitude of the car’s final velocity b.  the displacement of the car c.  the direction of the car’s final velocity d.  all of the above

11. A 3.00 kg toy falls from a height of 1.00 m. What will the kinetic energy of the toy be just before the toy hits the ground? (Assume no air resistance and that g = 9.81 m/s2 .)a.  9.8 J b.  3.00 J c.  29.4 J d.  294 J e.  0.98 J

12. Which of the following line segments on a position versus time graph is physically impossible?a.  a straight line that slopes to the left b.  a straight line that slopes to the right c.  a horizontal line d.  a vertical line

Name: ______________________ ID: A

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13. Which of the following is the equation for acceleration?

a.  vi − vf

ti − tf

b.  a =ΔtΔv

c.  a = ΔvΔt d.  a =ΔvΔt

14. The best way to measure objects the size of you textbook would be to usea.  kilometers b.  micrometers c.  milliliters d.  centimeters

15. A student walks from the door of the house to the end of the driveway and realizes that he missed the bus. The student runs back to the house, traveling three times as fast. Which of the following is the correct expression for the return velocity if the initial velocity is vstudent?a.   1

3vstudent b.  –3vstudent c.  3vstudent d.   1

3vstudent

16. What is the potential energy of a 1.0 kg mass 1.0 m above the ground?a.  10 J b.  96 J c.  9.8 N d.  9.8 J e.  1.0 J

17. Which of the following is the tendency of an object to maintain its state of motion?a.  inertia b.  force c.  acceleration d.  velocity

18. What is the kinetic energy of a 0.135 kg baseball thrown at 40.0 m/s?a.  87.0 J b.  54.0 J c.  108 J d.  5.4 J e.  216 J

19. The sun is composed mostly of hydrogen. The mass of the sun is 2.0 × 1030 kg, and the mass of a hydrogen atom is 1.67 × 10−27 kg. Estimate the number of atoms in the sun.a.  1030 b.  1075 c.  103 d.  1057

20. Calculate the following, and express the answer in scientific notation with the correct number of significant figures: (0.82 + 0.042)(4.4 × 103 )a.  3.78 × 103 b.  3.8 × 103 c.  3784 d.  3.784 × 103

21. A billiard ball collides with a stationary identical billiard ball in a perfectly elastic head-on collision. After the collision, which of the following is true of the first ball?a.  It comes to rest. b.  It moves in the opposite direction. c.  It has one-half its initial velocity. d.  It maintains its initial velocity.

22. Estimate the order of magnitude of the length of a football field.a.  10−1 m b.  104 m c.  106 m d.  102 m

23. If the mass in a horizontal mass-spring system was doubled, the elastic potential energy in the system would change by a factor ofa.  4. b.  0 (no change). c.  2. d.  1/2. e.  1/4.

24. Find the resultant of these two vectors: 2.00 × 102 units due east and 4.00 × 102 units 30.0° north of west.a.  546 units, 59.3° north of west b.  300 units, 29.8° north of west c.  248 units, 53.9° north of west d.  581 units, 20.1° north of east

25. A soccer ball collides with another soccer ball at rest. The total momentum of the ballsa.  remains constant. b.  is zero. c.  decreases. d.  increases.

Name: ______________________ ID: A

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26. The SI base unit for time isa.  1 day. b.  1 minute. c.  1 hour. d.  1 second.

27. Calculate the following, and express the answer in scientific notation with the correct number of significant figures: 21.4 + 15 + 17.17 + 4.003a.  5.8 × 101 b.  5.757 × 101 c.  5.7573 × 101 d.  5.75 × 101

28. What are the SI units for momentum?a.  J b.  kg•m/s2 c.  kg•m/s d.  N•m

29. A worker does 25 J of work lifting a bucket, then sets the bucket back down in the same place. What is the total net work done on the bucket?a.  –25 J b.  50 J c.  25 J d.  -50 J e.  0 J

30. What are the units for a spring constant?a.  N b.  N/m c.  m d.  J/m e.  N•m

31. Which of the following is not equal to 1.0 J?a.  1000 mJ b.  1.0 N m c.  1.0 W s d.  0.01 kJ e.  1.0 kg m2/s2

32. Gravitational potential energy is always measured in relation toa.  kinetic energy. b.  a zero level. c.  mechanical energy. d.  total potential energy.

33. If a nonzero net force is acting on an object, then the object is definitelya.  moving with a constant velocity. b.  losing mass. c.  being accelerated. d.  at rest.

34. What is the path of a projectile (in the absence of friction)?a.  a parabola b.  a wavy line c.  a hyperbola d.  Projectiles do not follow a predictable path.

35. A ball is dropped from a person’s hand and falls to Earth. Identify an action-reaction pair in this situation.a.  Earth exerts a force on the hand; the hand exerts a force on the ball. b.  The hand exerts a force on the ball; Earth exerts a force on the hand. c.  Earth exerts a force on the ball; the ball exerts a force on Earth. d.  Earth exerts a force on the ball; the hand exerts a force on Earth.

36. When a car’s velocity is positive and its acceleration is negative, what is happening to the car’s motion?a.  The car remains at rest. b.  The car slows down. c.  The car speeds up. d.  The car travels at constant speed.

37. The impulse experienced by a body is equivalent to the body’s change ina.  force. b.  momentum. c.  kinetic energy. d.  velocity.

38. Physics is the science that describesa.  how to make objects work b.  the way atoms interact with each other c.  how to build objects d.  the physical world

39. A scale, even when on an accelerating elevator, measuresa.  normal force b.  gravitation force. c.  mass d.  angle of contact

40. Which would hit the ground first if dropped from the same height in a vacuum—a feather or a metal bolt?a.  They would be suspended in a vacuum. b.  the feather c.  the metal bolt d.  They would hit the ground at the same time.

41. A 0.2 kg baseball is pitched with a velocity of 40 m/s and is then batted to the pitcher with a velocity of 60 m/s. What is the magnitude of change in the ball’s momentum?a.  20 kg•m/s b.  4 kg•m/s c.  2 kg•m/s d.  8 kg•m/s

Name: ______________________ ID: A

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42. Calculate the following, and express the answer in scientific notation with the correct number of significant figures: 10.5 × 8.8 × 3.14

a.  290 b.  2.90 × 102 c.  2.9 × 102 d.  290.136

43. Which of the following energy forms is associated with an object in motion?a.  nonmechanical energy b.  kinetic energy c.  gravitational potential energy d.  potential energy e.  elastic potential energy

44. An ant on a picnic table travels 3.0 × 101 cm eastward, then 25 cm northward, and finally 15 cm westward. What is the magnitude of the ant’s displacement relative to its original position?a.  52 cm b.  70 cm c.  29 cm d.  57 cm

45. For the winter, a duck flies 10.0 m/s due south against a gust of wind with a speed of 2.5 m/s. What is the resultant velocity of the duck?a.  –7.5 m/s south b.  7.5 m/s south c.  –12.5 m/s south d.  12.5 m/s south

46. Which of the following is not an example of projectile motion?a.  a hot-air balloon drifting in the air b.  a long jumper in action c.  a baseball hit by a bat d.  a volleyball served over a net

47. Multiplying or dividing vectors by scalars results ina.  scalars if multiplied or vectors if divided. b.  vectors. c.  vectors if multiplied or scalars if divided. d.  scalars.

48. Three values were obtained for the mass of a metal bar: 8.83 g; 8.84 g; 8.82 g. The known mass is 10.68 g. The values area.  accurate. b.  precise. c.  both accurate and precise. d.  neither accurate nor precise.

49. A net force of 6.8 N accelerates a 31 kg scooter across a level parking lot. What is the magnitude of the scooter’s acceleration?a.  3.2 m/s2 b.  0.69 m/s2 c.  0.22 m/s2 d.  4.6 m/s2

50. A ball with a momentum of 4.0 kg•m/s hits a wall and bounces straight back without losing any kinetic energy. What is the change in the ball’s momentum?a.  –8.0 kg•m/s b.  8.0 kg•m/s c.  0.0 kg•m/s d.  –4.0 kg•m/s

51. A newton is equivalent to which of the following quantities?a.  kg•(m/s)2 b.  kg•m/s2 c.  kg•m/s d.  kg

52. Which of the following has the greatest momentum?a.  a roadrunner with a mass of 1.8 kg moving at a velocity of 6.7 m/s b.  a hare with a mass of 2.7 kg moving at a velocity of 7.5 m/s c.  a tortoise with a mass of 275 kg moving at a velocity of 0.55 m/s d.  a turtle with a mass of 91 kg moving at a velocity of 1.4 m/s

53. Which of the following equations expresses the work-kinetic energy theorem?a.  W net = ΔKE b.  W net = ΔPE c.  MEi = MEf d.  ΔW = ΔKE e.  none of the above

54. The coefficient of static friction is alwaysa.  less than the coefficient of kinetic friction b.  equal to the coefficient of kinetic friction c.  greater than the coefficient of kinetic friction d.  equal to the normal force

ID: A

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PHYSICS First Half of the Year ReviewAnswer Section

MULTIPLE CHOICE

1. ANS: C DIF: II OBJ: 2-2.2 2. ANS: A DIF: II OBJ: 6-1.1 3. ANS: D DIF: I OBJ: 2-1.3 4. ANS: A

Givenk = 10.0 N/m

x = 2.00 m

SolutionPE =

1

2kx2 =

1

210.0 N/m( ) 2.00 m( ) 2 = 20.0 J

DIF: IIIA OBJ: 5-2.6 5. ANS: C DIF: I OBJ: 6-1.3 6. ANS: B DIF: I OBJ: 1-2.1 7. ANS: C DIF: I OBJ: 4-4.4 8. ANS: A DIF: I OBJ: 6-3.1 9. ANS: D DIF: I OBJ: 4-4.1 10. ANS: D DIF: I OBJ: 2-2.1 11. ANS: C

Givenm = 3.00 kg

h = 1.00 m

g = 9.81 m/s 2

SolutionKEf = PEg, i = mgh = 3.00 kgÊ

ËÁÁˆ¯̃̃ 9.81 m/s 2ÊËÁÁÁÁ

ˆ¯˜̃̃˜ 1.00 m( ) = 29.4 J

DIF: IIIA OBJ: 5-3.3 12. ANS: D DIF: II OBJ: 2-1.3 13. ANS: D DIF: I OBJ: 2-2.1 14. ANS: D DIF: I OBJ: 1-2.3 15. ANS: B DIF: II OBJ: 3-1.3

ID: A

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16. ANS: D

Givenm = 1.0 kg

h = 1.0 m

g = 9.81 m/s 2

SolutionPE = mgh = 1.0 kgÊ

ËÁÁˆ¯̃̃ 9.81 m/s 2ÊËÁÁÁÁ

ˆ¯˜̃̃˜ 1.0 m( ) = 9.8 J

DIF: IIIA OBJ: 5-2.6 17. ANS: A DIF: I OBJ: 4-2.1 18. ANS: C

Givenm = 0.135 kg

v = 40.0 m/s

SolutionKE =

1

2mv2 =

1

2(0.135kg)(40.0m / s)2 = 108J

DIF: IIIA OBJ: 5-2.2 19. ANS: D

Given

m sun = 2.0 × 1030 kg

m H atom = 1.67 × 10−27 kg

Solution

Estimate the answer using an order-of-magnitude calculation.

1030

10−27= 1057

DIF: IIIB OBJ: 1-3.4

ID: A

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20. ANS: BSolution0.82 + 0.042( ) 4.4 × 103Ê

ËÁÁÁÁ

ˆ¯˜̃̃˜ = 0.86( ) 4.4 × 103Ê

ËÁÁÁÁ

ˆ¯˜̃̃˜ = 3784

The answer rounds to 3800 and is written as 3.8 × 103 in scientific notation.

DIF: IIIA OBJ: 1-2.4 21. ANS: A DIF: I OBJ: 6-3.3 22. ANS: D DIF: II OBJ: 1-3.4 23. ANS: B DIF: II OBJ: 5-2.6 24. ANS: C

Givend 1 = 2.00 × 102 units east

d 2 = 4.00 × 102 units 30.0° north of west

SolutionMeasuring direction with respect to x = (east),Δx1 = 2.00 × 102 units

Δy1 = 0

Δx2 = d2 cosθ = (4.00 × 102 units)(cos 150.0°) = −3.46 × 102 units

Δy2 = d2 sinθ = (4.00 × 102 units)(sin 150.0°) = 2.00 × 102 units

Δxtot = Δx1 + Δx2 = (2.00 × 102 units) + (−3.46 × 102 units) = −1.46 × 102 units

Δytot = Δy1 + Δy2 = 0 + (2.00 × 102 units) = 2.00 × 102 units

d2 = (Δxtot)2 + (Δytot)

2

d = (Δxtot)2 + (Δytot)

2 = (−1.46 × 102 units)2 + (2.00 × 102 units)2

d = 2.48 × 102 units

θ = tan−1Δytot

Δxtot

Ê

Ë

ÁÁÁÁÁÁÁÁÁÁ

ˆ

¯

˜̃̃˜̃̃˜̃̃˜

= tan−1 2.00 × 102 units–1.46 × 102 units

Ê

Ë

ÁÁÁÁÁÁÁÁÁÁ

ˆ

¯

˜̃̃˜̃̃˜̃̃˜

= −53.9°

d = 2.48 × 102 units,53.9°north of west

DIF: IIIB OBJ: 3-2.4 25. ANS: A DIF: I OBJ: 6-2.2 26. ANS: D DIF: I OBJ: 1-2.1

ID: A

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27. ANS: ASolution

21.4

15.

17.17

+4.003

57.573

Answer rounds to 58 and is written as 5.8 × 101 in scientific notation.

DIF: IIIA OBJ: 1-2.4 28. ANS: C DIF: I OBJ: 6-1.1 29. ANS: E DIF: II OBJ: 5-1.3 30. ANS: B DIF: I OBJ: 5-2.6 31. ANS: D DIF: II OBJ: 5-2.2 32. ANS: B DIF: I OBJ: 5-2.5 33. ANS: C DIF: I OBJ: 4-3.1 34. ANS: A DIF: I OBJ: 3-3.2 35. ANS: C DIF: II OBJ: 4-3.3 36. ANS: B DIF: II OBJ: 2-2.1 37. ANS: B DIF: I OBJ: 6-1.4 38. ANS: D DIF: I OBJ: 1-1.2 39. ANS: A DIF: II OBJ: 4-2.3 40. ANS: D DIF: I OBJ: 2-3.3 41. ANS: A

Givenm = 2.0 kg

vi = 40 m/s

vf = −60 m/s

SolutionΔp = m vf − vi

ÊËÁÁ ˆ

¯˜̃ = 0.2 kgÊ

ËÁÁˆ¯̃̃ −60 m/s − 40 m/s( ) = −20 kgm/s

DIF: IIIA OBJ: 6-1.3 42. ANS: C

Solution10.5( ) × 8.8( ) × 3.14( ) = 290.136

The answer rounds to 290 and is written as 2.9 × 102 in scientific notation.

DIF: IIIA OBJ: 1-2.4

ID: A

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43. ANS: B DIF: I OBJ: 5-2.1 44. ANS: C

GivenΔx1 = 3.0 × 101 cmΔy1 = 25 cmΔx2 = –15 cm

SolutionΔxtot = Δx1 + Δx2 = (3.0 × 101 cm) + ( − 15 cm) = 15 cm

Δytot = Δy1 = 25 cm

d2 = (Δxtot)2 + (Δytot)

2

d = (Δxtot)2 + (Δytot)

2 = (15 cm)2 + (25 cm)2

d = 29 cm

DIF: IIIA OBJ: 3-2.2 45. ANS: B

Givenv1 = 10.0 m/s southv2 = 2.5 m/s north

SolutionvR = v1 − v2 = 10.0 m/s − 2.5 m/s = 7.5 m/svR = 7.5 m/s south

DIF: IIIA OBJ: 3-1.2 46. ANS: A DIF: I OBJ: 3-3.1 47. ANS: B DIF: I OBJ: 3-1.3 48. ANS: B DIF: II OBJ: 1-2.3

ID: A

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49. ANS: C

GivenFapplied = 6.8 Nm = 31 kg

SolutionFnet = Fx = Fapplied = max∑

ax =Fapplied

m=

6.8 N31 kg

= 0.22 m/s 2

DIF: IIIA OBJ: 4-3.2 50. ANS: A

Givenpi = 4.0 kgm/s

pf = −4.0 kgm/s

SolutionΔp = pf − pi = −4.0 kgm/sÊ

ËÁÁˆ¯̃̃ − 4.0 kgm/s = −8.0 kgm/s

DIF: II OBJ: 6-1.3 51. ANS: B DIF: I OBJ: 4-1.1

ID: A

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52. ANS: C

Givena: m = 275 kg

v = 0.55 m/sb: m = 2.7 kg

v = 7.5 m/sc: m = 91 kg

v = 1.4 m/sd: m = 1.8 kg

v = 6.7 m/s

Solutionp = mv

p a = 275 kgÊËÁÁ

ˆ¯̃̃ 0.55 m/s( ) = 1.5 × 102 kgm/s

p b = 2.7 kgÊËÁÁ

ˆ¯̃̃ 7.5 m/s( ) = 2.0 × 101 kgm/s

p c = 91 kgÊËÁÁ

ˆ¯̃̃ 1.4 m/s( ) = 1.3 × 102 kgm/s

p d = 1.8 kgÊËÁÁ

ˆ¯̃̃ 6.7 m/s( ) = 1.2 × 101 kgm/s

p a > p c > p b > p d

DIF: IIIA OBJ: 6-1.1 53. ANS: A DIF: I OBJ: 5-2.3 54. ANS: C DIF: I OBJ: 4-4.1