Physics Midterm Review KEY Name: Date...A 0.0600-kilogram ball traveling at 60.0 meters per second hits a concrete wall. What speed must a 0.0100-kilogram bullet have in order to hit

Physics Midterm Review KEY

Name: Date:

1. Which quantities are scalar?

A. speed and work

B. velocity and force

C. distance and acceleration

D. momentum and power

2. A 160.-kilogram space vehicle is traveling along astraight line at a constant speed of 800. meters persecond. The magnitude of the net force on thespace vehicle is

A. 0 N B. 1.60 × 102 N

C. 8.00 × 102 N D. 1.28 × 105 N

3. A student throws a 5.0-newton ball straight up.What is the net force on the ball at its maximumheight?

A. 0.0 N B. 5.0 N, up

C. 5.0 N, down D. 9.8 N, down

4. A vertical spring has a spring constant of100. newtons per meter. When an object isattached to the bottom of the spring, the springchanges from its unstretched length of 0.50 meterto a length of 0.65 meter. The magnitude of theweight of the attached object is

A. 1.1 N B. 15 N C. 50. N D. 65 N

5. A 1.5-kilogram cart initially moves at 2.0 metersper second. It is brought to rest by a constant netforce in 0.30 second. What is the magnitude ofthe net force?

A. 0.40 N B. 0.90 N

C. 10. N D. 15 N

6. As a 5.0 × 102–newton basketball player jumpsfrom the floor up toward the basket, the magnitudeof the force of her feet on the floor is 1.0 × 103

newtons. As she jumps, the magnitude of theforce of the floor on her feet is

A. 5.0 × 102 N B. 1.0 × 103 N

C. 1.5 × 103 N D. 5.0 × 105 N

7. A 0.0600-kilogram ball traveling at 60.0 metersper second hits a concrete wall. What speed musta 0.0100-kilogram bullet have in order to hit thewall with the same magnitude of momentum asthe ball?

A. 3.60 m/s B. 6.00 m/s

C. 360. m/s D. 600. m/s

8. The Hubble telescope’s orbit is 5.6 × 105 metersabove Earth’s surface. The telescope has a massof 1.1 × 104 kilograms. Earth exerts a gravitationalforce of 9.1 × 104 newtons on the telescope. Themagnitude of Earth’s gravitational field strength atthis location is

A. 1.5 × 10−20 N/kg B. 0.12 N/kg

C. 8.3 N/kg D. 9.8 N/kg

9. A block slides across a rough, horizontal tabletop.As the block comes to rest, there is an increase inthe block-tabletop system’s

A. gravitational potential energy

B. elastic potential energy

C. kinetic energy

D. internal (thermal) energy

page 1

10. Which diagram best represents the position of aball, at equal time intervals, as it falls freely fromrest near Earth’s surface?

A. B. C. D.

11. A different force is applied to each of four differentblocks on a frictionless, horizontal surface. Inwhich diagram does the block have the greatestinertia 2.0 seconds after starting from rest?

A.

B.

C.

D.

12. The diameter of an automobile tire is closest to

A. 10−2 m B. 100 m

C. 101 m D. 102 m

13. Without air resistance, a kicked ball would reach amaximum height of 6.7 meters and land 38 metersaway. With air resistance, the ball would travel

A. 6.7 m vertically and more than 38 mhorizontally

B. 38 m horizontally and less than 6.7 mvertically

C. more than 6.7 m vertically and less than 38 mhorizontally

D. less than 38 m horizontally and less than6.7 m vertically

14. A car is moving with a constant speed of20. meters per second. What total distance doesthe car travel in 2.0 minutes?

A. 10. m B. 40. m

C. 1200 m D. 2400 m

15. A car, initially traveling at 15 meters per secondnorth, accelerates to 25 meters per second northin 4.0 seconds. The magnitude of the averageacceleration is

A. 2.5 m/s2 B. 6.3 m/s2

C. 10. m/s2 D. 20. m/s2

16. An object is in equilibrium. Which force vectordiagram could represent the force(s) acting on theobject?

A. B.

C. D.

page 2 Physics Midterm Review KEY

17. Which graph best represents the relationshipbetween the potential energy stored in a springand the change in the spring’s length from itsequilibrium position?

A.

B.

C.

D.

18. An electric motor has a rating of 4.0 × 102 watts.How much time will it take for this motor tolift a 50.-kilogram mass a vertical distance of8.0 meters? [Assume 100% efficiency.]

A. 0.98 s B. 9.8 s C. 98 s D. 980 s

19. A compressed spring in a toy is used to launch a5.00-gram ball. If the ball leaves the toy with aninitial horizontal speed of 5.00 meters per second,the minimum amount of potential energy stored inthe compressed spring was

A. 0.0125 J B. 0.0250 J

C. 0.0625 J D. 0.125 J

20. Which combination of fundamental units can beused to express the amount of work done on anobject?

A. kg·m/s B. kg·m/s2

C. kg·m2/s2 D. kg·m2/s3

21. Calculate the minimum power output of an electricmotor that lifts a 1.30 × 104-newton elevatorcar vertically upward at a constant speed of1.50 meters per second. [Show all work, includingthe equation and substitution with units.]


22. Base your answer(s) to the following question(s) on the information and diagram below and on your knowledge ofphysics.

A 1.5 × 103-kilogram car is driven at a constant speed of 12 meters per second counterclockwise arounda horizontal circular track having a radius of 50. meters, as represented below.

Track, as Viewed from Above

On the diagram provided, draw an arrow to indicate the direction of the velocity of the car when it is at theposition shown. Start the arrow on the car.

23. Calculate the magnitude of the centripetal acceleration of the car. [Show all work, including the equation andsubstitution with units.]


24. Base your answer(s) to the following question(s)on the information below and on your knowledgeof physics.

A football is thrown at an angle of30.◦ above the horizontal. The magnitudeof the horizontal component of the ball’sinitial velocity is 13.0 meters per second.The magnitude of the vertical component ofthe ball’s initial velocity is 7.5 meters persecond. [Neglect friction.]

On the axes provided, draw a graph representingthe relationship between the horizontaldisplacement of the football and the time thefootball is in the air.


The diagram below represents a4.0-newton force applied to a 0.200-kilogramcopper block sliding to the right on ahorizontal steel table.

Determine the weight of the block.

26. Calculate the magnitude of the force of frictionacting on the moving block. [Show all work,including the equation and substitution with units.]

27. Determine the magnitude of the net force actingon the moving block.

28. Describe what happens to the magnitude of thevelocity of the block as the block slides across thetable.

29. Two 20.-newton forces act concurrently on anobject. What angle between these forces willproduce a resultant force with the greatestmagnitude?

A. 0◦ B. 45◦ C. 90.◦ D. 180.◦

30. In a race, a runner traveled 12 meters in4.0 seconds as she accelerated uniformly from rest.The magnitude of the acceleration of the runnerwas

A. 0.25 m/s2 B. 1.5 m/s2

C. 3.0 m/s2 D. 48 m/s2

31. A projectile is launched at an angle abovethe ground. The horizontal component of theprojectile’s velocity, vx, is initially 40. meters persecond. The vertical component of the projectile’svelocity, vy, is initially 30. meters per second.What are the components of the projectile’svelocity after 2.0 seconds of flight? [Neglectfriction.]

A. vx = 40.m/s and vy = 10.m/s

B. vx = 40.m/s and vy = 30.m/s

C. vx = 20.m/s and vy = 10.m/s

D. vx = 20.m/s and vy = 30.m/s

32. A ball is thrown with an initial speed of 10. metersper second. At what angle above the horizontalshould the ball be thrown to reach the greatestheight?

A. 0◦ B. 30.◦ C. 45◦ D. 90.◦

33. Which object has the greatest inertia?

A. a 0.010-kg bullet traveling at 90. m/s

B. a 30.-kg child traveling at 10. m/s on her bike

C. a 490-kg elephant walking with a speed of1.0 m/s

D. a 1500-kg car at rest in a parking lot


34. An 8.0-newton wooden block slides across ahorizontal wooden floor at constant velocity. Whatis the magnitude of the force of kinetic frictionbetween the block and the floor?

A. 2.4 N B. 3.4 N C. 8.0 N D. 27 N

35. Which situation represents a person in equilibrium?

A. a child gaining speed while sliding down aslide

B. a woman accelerating upward in an elevator

C. a man standing still on a bathroom scale

D. a teenager driving around a corner in his car

36. A rock is thrown straight up into the air. At thehighest point of the rock’s path, the magnitude ofthe net force acting on the rock is

A. less than the magnitude of the rock’s weight,but greater than zero

B. greater than the magnitude of the rock’sweight

C. the same as the magnitude of the rock’sweight

D. zero

37. The diagram below shows a compressed springbetween two carts initially at rest on a horizontal,frictionless surface. Cart A has a mass of2 kilograms and cart B has a mass of 1 kilogram.A string holds the carts together.

The string is cut and the carts move apart.Compared to the magnitude of the force the springexerts on cart A, the magnitude of the force thespring exerts on cart B is

A. the same B. half as great

C. twice as great D. four times as great

38. An 8.0-newton block is accelerating down africtionless ramp inclined at 15◦ to the horizontal,as shown in the diagram below.

What is the magnitude of the net force causingthe block’s acceleration?

A. 0 N B. 2.1 N C. 7.7 N D. 8.0 N

39. At a certain location, a gravitational forcewith a magnitude of 350 newtons acts on a70.-kilogram astronaut. What is the magnitude ofthe gravitational field strength at this location?

A. 0.20 kg/N B. 5.0 N/kg

C. 9.8 m/s2 D. 25 000 N ·kg

40. The approximate length of an unsharpened No. 2pencil is

A. 2.0 × 10−2 m B. 2.0 × 10−1 m

C. 2.0 × 100 m D. 2.0 × 101 m

41. The diagram below shows an 8.0-kilogram cartmoving to the right at 4.0 meters per second aboutto make a head-on collision with a 4.0-kilogramcart moving to the left at 6.0 meters per second.

After the collision, the 4.0-kilogram cart movesto the right at 3.0 meters per second. What isthe velocity of the 8.0-kilogram cart after thecollision?

A. 0.50 m/s left B. 0.50 m/s right

C. 5.5 m/s left D. 5.5 m/s right


42. Four forces act concurrently on a block on ahorizontal surface as shown in the diagram below.

As a result of these forces, the block

A. moves at constant speed to the right

B. moves at constant speed to the left

C. accelerates to the right

D. accelerates to the left

43. If a motor lifts a 400.-kilogram mass a verticaldistance of 10. meters in 8.0 seconds, the minimumpower generated by the motor is

A. 3.2 × 102 W B. 5.0 × 102 W

C. 4.9 × 103 W D. 3.2 × 104 W

44. A 4.0-kilogram object is accelerated at 3.0 metersper second2 north by an unbalanced force. Thesame unbalanced force acting on a 2.0-kilogramobject will accelerate this object toward the northat

A. 12 m/s2 B. 6.0 m/s2

C. 3.0 m/s2 D. 1.5 m/s2

45. Which graph represents the relationship betweenthe kinetic energy and the speed of a freely fallingobject?

A.

B.

C.

D.


46. Which graph represents the relationship betweenthe magnitude of the gravitational force, Fg,between two masses and the distance, r, betweenthe centers of the masses?

A.

B.

C.

D.

47. Base your answer(s) to the following question(s)on the information on the graph below.

The graph shows the relationshipbetween speed and elapsed time for a carmoving in a straight line.

Determine the magnitude of the acceleration of thecar.

48. Calculate the total distance the car traveled duringthe time interval 4.0 seconds to 8.0 seconds.

49. Base your answer(s) to the following question(s)on the information below.

A 28-gram rubber stopper is attachedto a string and whirled clockwise in ahorizontal circle with a radius of 0.80 meter.The diagram in your answer bookletrepresents the motion of the rubber stopper.The stopper maintains a constant speed of2.5 meters per second.

Calculate the magnitude of the centripetalacceleration of the stopper.


50. On the diagram below, draw an arrow showing thedirection of the centripetal force acting on thestopper when it is at the position shown.

51. Base your answer(s) to the following question(s)on the information and diagram below.

A 30.4-newton force is used to slide a40.0-newton crate a distance of 6.00 metersat constant speed along an incline to avertical height of 3.00 meters.

Determine the total work done by the 30.4-newtonforce in sliding the crate along the incline.


A 30.4-newton force is used to slide a40.0-newton crate a distance of 6.00 metersat constant speed along an incline to avertical height of 3.00 meters.

Determine the total work done by the 30.4-newtonforce in sliding the crate along the incline.

53. Calculate the total increase in the gravitationalpotential energy of the crate after it has slid6.00 meters along the incline.

54. State what happens to the kinetic energy of thecrate as it slides along the incline.

55. State what happens to the internal energy of thecrate as it slides along the incline.

56. A 100-kilogram person acquires a velocity of15 meters per second down a ski slope. What isthe skier’s kinetic energy?

A. 22,500 joules B. 11,250 joules

C. 1,500 joules D. 115 joules

57. A 75-kilogram boy initially at rest skis down theslope as shown. Assuming no frictional loss, whatwill be his kinetic energy at the bottom of theslope?

A. 1,500 joules B. 7,500 joules

C. 15,000 joules D. 75,000 joules


58. As a falling apple approaches the ground, itspotential energy

A. decreases B. increases

C. remains the same

59. A cart weighing 10 newtons is pushed 10 meterson a level surface by a force of 5 newtons. Whatis the increase in its potential energy?

A. 1 joule B. 50 joules

C. 100 joules D. 0 joules

60. A “push or pull” best describes the term

A. work B. momentum

C. potential energy D. force

61. The diagram here shows a 1-kilogram stone beingdropped from a bridge 100 meters above a gorge.

As the stone falls, the gravitational potentialenergy of the stone

A. decreases B. increases

C. remains the same

62. Each of the blocks in the diagrams is liftedvertically for the distance indicated. Which blockwill gain the most gravitational potential energy?

A.

B.

C.

D.

63. One joule is equivalent to one

A.newton

meter3B. kilogram-meter3

C. watt2-newton D.kilogram-meter3

second2


64. The diagram shown represents two objects at reston a frictionless horizontal surface with a springcompressed between them. When the compressedspring is released, the two objects are pushedapart.

What kinetic energy does the 2.0-kilogram objecthave after gaining a velocity of 5.0 meters persecond?

A. 25 J B. 20 J C. 10 J D. 5.0 J

65. The diagram shown here represents a blocksuspended from a spring. The spring is stretched0.200 meter. If the spring constant is 200 newtonsper meter, what is the weight of the block?

A. 40.0 N B. 20.0 N

C. 8.00 N D. 4.00 N

66. A 0.10-meter spring is stretched from equilibriumto position A and then to position B as shown inthe diagram. Compared to the spring’s potentialenergy at A, what is its potential energy at B ?

A. the same B. twice as great

C. half as great D. four times as great

67. The sum of the kinetic and potential energies ofan object’s molecules is called the object’s

A. temperature B. heat of fusion

C. internal energy D. specific heat

68. What is the spring constant of a spring ofnegligible mass which gained 8 joules of potentialenergy as a result of being compressed 0.4 meter?

A. 100 N/m B. 50 N/m

C. 0.3 N/m D. 40 N/m

69. The graph represents the relationship between theforce applied to a spring and the elongation of thespring. What is the spring constant?

A. 20 N/m B. 9.8 N/kg

C. 0.80 N · m D. 0.050 m/N

70. An object 10 meters above the ground has Z joulesof potential energy. If the object falls freely, howmany joules of kinetic energy will it have gainedwhen it is 5 meters above the ground?

A. Z B. 2Z C.Z2

D. 0

71. Which quantity and unit are correctly paired?

A. velocity: m/s2

B. momentum:kg · m

s2

C. energy:kg · m2

s2

D. work: kg/m


72. Three people of equal mass climb a mountainusing paths A, B, and C shown in the diagram.Along which path(s) does a person gain thegreatest amount of gravitational potential energyfrom start to finish?

A. A, only

B. B, only

C. C, only

D. The gain is the same along all paths.

73. The graph shows the elongation of a spring as afunction of the force. What is the value of thespring constant?

A. 0.1 m/N

B. 0.1 N/m

C. 10 m/N

D. 10 N/m

74. A box weighing 1.0 × 102 newtons is dragged tothe top of an incline, as shown in the diagram.The gravitational potential energy of the box at thetop of the incline is approximately

A. 1.0 × 102 J B. 6.0 × 102 J

C. 8.0 × 102 J D. 1.0 × 103 J

75. A 20-newton weight is attached to a spring,causing it to stretch, as shown in the diagram.What is the spring constant of this spring?

A. 0.050 N/m B. 0.25 N/m

C. 20 N/m D. 40 N/m

76. The accompanying diagram shows block A, havingmass 2m and speed v, and block B having massm and speed 2v.

Compared to the kinetic energy of block A, thekinetic energy of block B is

A. the same B. twice as great

C. one-half as great D. four times as great

77. A spring has a spring constant of 120 newtons permeter. How much potential energy is stored in thespring as it is stretched 0.20 meter?

A. 2.4 J B. 4.8 J C. 12 J D. 24 J


78. Which graph best represents the elastic potentialenergy stored in a spring (PEs) as a function ofits elongation, x?

A.

B.

C.

D.

79. Base your answer(s) to the following question(s)on the information and table below.

The table lists the kinetic energy of a4.0-kilogram mass as it travels in a straightline for 12.0 seconds.

Time(seconds)

Kinetic Energy(joules)

0.0 0.0

2.0 8.0

4.0 18

6.0 32

10.0 32

12.0 32

Mark an appropriate scale on the axis labeled“Kinetic Energy (J).”

80. Plot the data points for kinetic energy versus time.


81. What is the total electrical energy used by a1500-watt hair dryer operating for 6.0 minutes?

A. 4.2 J B. 250 J

C. 9.0 × 103 J D. 5.4 × 105 J

82. If the speed of a car is doubled, the kinetic energyof the car is

A. quadrupled B. doubled

C. quartered D. halved


A 1000.-kilogram empty cart moving with a speedof 6.0 meters per second is about to collide with astationary loaded cart having a total mass of 5000.kilograms, as shown. After the collision, thecarts lock and move together. [Assume friction isnegligible.]

How does the kinetic energy of the combined cartsafter the collision compare to the kinetic energy ofthe carts before the collision?

84. How much work is required to lift a 2-kilogrammass to a height of 10 meters?

A. 5 joules B. 20 joules


85. How much work is done on a 300-newton suitcaseto lift it 0.50 meter?

A. 600 joules B. 300 joules


86. A machine is able to do 30 joules of work in6.0 seconds. The power developed by the machineis

A. 0.20 watt B. 0.50 watt

C. 5.0 watts D. 180 watts

87. How much work will a 500-watt motor do in10 seconds?

A. 0.02 joule B. 50 joules

C. 500 joules D. 5,000 joules

88. In the diagram, 55 joules of work is needed toraise a 10-newton weight 5.0 meters at a constantspeed. How much work is done to overcomefriction as the weight is raised?

A. 5 J B. 5.5 J

C. 11 J D. 50 J

89. The graph shows the force exerted on a blockas a function of the block’s displacement in thedirection of the force. How much work did theforce do in displacing the block 5.0 meters?

A. 0 J B. 20 J C. 0.80 J D. 4.0 J


90. As shown in the diagram, pulling a 9.8-newtoncart a distance of 0.50 meter along a planeinclined at 15◦ requires 1.3 joules of work. If thecart were raised 0.50 meter vertically instead ofbeing pulled along the inclined plane, the amountof work would be

A. less

B. greater

C. the same

91. A 45-kilogram bicyclist climbs a hill at a constantspeed of 2.5 meters per second by applying anaverage force of 85 newtons. Approximately howmuch power does the bicyclist develop?

A. 110 W B. 210 W

C. 1100 W D. 1400 W

92. The accompanying diagram shows two identicalwooden planks, A and B, at different inclineangles, used to slide concrete blocks from a truck.

Compared to the amount of work done againstfriction by a block sliding down plank A, thework done against friction by a block sliding downplank B is

A. less B. more C. the same

93. A 10.-newton force is required to move a3.0-kilogram box at constant speed. How muchpower is required to move the box 8.0 meters in2.0 seconds?

A. 40. W B. 20. W C. 15 W D. 12 W


A 160.-newton box sits on a10.-meter-long frictionless plane inclined atan angle of 30.◦ to the horizontal as shown.Force (F) applied to a rope attached to thebox causes the box to move with a constantspeed up the incline.

Calculate the amount of work done in moving thebox from the bottom to the top of the inclinedplane. [Show all work, including the equation andsubstitution with units.]



Using a spring toy like the oneshown in the diagram, a physics teacherpushes on the toy, compressing thespring, causing the suction cup to stickto the base of the toy.

When the teacher removes herhand, the toy pops straight up and justbrushes against the ceiling. She doesthis demonstration five times, alwayswith the same result.

When the teacher repeats thedemonstration for the sixth time thetoy crashes against the ceiling withconsiderable force. The students noticethat in this trial, the spring and toyseparated from the base at the momentthe spring released.

The teacher puts the toy backtogether, repeats the demonstration andthe toy once again just brushes againstthe ceiling.

Describe the conversions that take place betweenpairs of the three forms of mechanical energy,beginning with the work done by the teacher onthe toy and ending with the form(s) of energypossessed by the toy as it hits the ceiling. [Neglectfriction.]

96. Explain, in terms of mass and energy, why thespring toy hits the ceiling in the sixth trial andnot in the other trials.

97. A 3.0-kilogram block is initially at rest on africtionless, horizontal surface. The block ismoved 8.0 meters in 2.0 seconds by the applicationof a 12-newton horizontal force, as shown in theaccompanying diagram.

What is the average power developed while movingthe block?

A. 24 W B. 32 W C. 48 W D. 96 W

98. One watt is equivalent to one

A. N · m B. N/m C. J · s D. J/s

99. As shown in the diagram below, a child appliesa constant 20.-newton force along the handleof a wagon which makes a 25◦ angle with thehorizontal.

How much work does the child do in moving thewagon a horizontal distance of 4.0 meters?

A. 5.0 J B. 34 J C. 73 J D. 80. J

100. Student A lifts a 50.-newton box from the floor toa height of 0.40 meter in 2.0 seconds. Student Blifts a 40.-newton box from the floor to a height of0.50 meter in 1.0 second. Compared to student A,student B does

A. the same work but develops more power

B. the same work but develops less power

C. more work but develops less power

D. less work but develops more power


101. A hiker travels 1.0 kilometer south, turns andtravels 3.0 kilometers west, and then turns andtravels 3.0 kilometers north. What is the totaldistance traveled by the hiker?

A. 3.2 km B. 3.6 km

C. 5.0 km D. 7.0 km

102. A car with an initial velocity of 16.0 metersper second east slows uniformly to 6.0 metersper second east in 4.0 seconds. What is theacceleration of the car during this 4.0-secondinterval?

A. 2.5 m/s2 west B. 2.5 m/s2 east

C. 4.0 m/s2 west D. 4.0 m/s2 east

103. On the surface of planet X, a body with a mass of10. kilograms weighs 40. newtons. The magnitudeof the acceleration due to gravity on the surfaceof planet X is

A. 4.0 × 103 m/s2 B. 4.0 × 102 m/s2

C. 9.8 m/s2 D. 4.0 m/s2

104. A car traveling in a straight line at an initial speedof 8.0 meters per second accelerates uniformly toa speed of 14 meters per second over a distanceof 44 meters. What is the magnitude of theacceleration of the car?

A. 0.41 m/s2 B. 1.5 m/s2

C. 3.0 m/s2 D. 2.2 m/s2

105. An electron in a magnetic field travels at constantspeed in the circular path represented in thediagram below.

Which arrow represents the direction of the netforce acting on the electron when the electron isat position A?

A. B.

C. D.

106. The graph below represents the relationshipbetween velocity and time of travel for a toy carmoving in a straight line.

The shaded area under the line represents the toycar’s

A. displacement B. momentum

C. acceleration D. speed

107. A spring stores 10. joules of elastic potentialenergy when it is compressed 0.20 meter. What isthe spring constant of the spring?

A. 5.0 × 101 N/m B. 1.0 × 102 N/m

C. 2.5 × 102 N/m D. 5.0 × 102 N/m


108. Base your answer to the following question on theinformation below and on your knowledge ofphysics.

A cannonball with a mass of1.0 kilogram is fired horizontally from a500.-kilogram cannon, initially at rest, ona horizontal, frictionless surface. Thecannonball is acted on by an average force of8.0 × 103 newtons for 1.0 × 10−1 second.

What is the magnitude of the change in momentumof the cannonball during firing?

A. 0 kg ·m/s B. 8.0 × 102 kg ·m/s

C. 8.0 × 103 kg ·m/s D. 8.0 × 104 kg ·m/s

109. What is the magnitude of the average net forceacting on the cannon?

A. 1.6 N B. 16 N

C. 8.0 × 103 N D. 4.0 × 106 N

110. A constant eastward horizontal force of70. newtons is applied to a 20.-kilogram cratemoving toward the east on a level floor. If thefrictional force on the crate has a magnitude of10. newtons, what is the magnitude of the crate’sacceleration?

A. 0.50 m/s2 B. 3.5 m/s2

C. 3.0 m/s2 D. 4.0 m/s2


Base your answer to the following question on the information and diagram below and on your knowledge of physics.

The graph below represents the speed of a marble rolling down a straight incline as a function of time.


111. Calculate the distance the marble travels duringthe first 3.0 seconds.

112. Base your answer to the following question on theinformation below and on your knowledge ofphysics.

A ball is rolled twice across the samelevel laboratory table and allowed to roll offthe table and strike the floor. In each trial,the time it takes the ball to travel from theedge of the table to the floor is accuratelymeasured. [Neglect friction.]

In trial A, the ball is traveling at 2.50 meters persecond when it reaches the edge of the table. Theball strikes the floor 0.391 second after rolling offthe edge of the table. Calculate the height of thetable.

113. In trial B, the ball is traveling at 5.00 meters persecond when it reaches the edge of the table.Compare the time it took the ball to reach thefloor in trial B to the time it took the ball to reachthe floor in trial A.

114. A 3.00-kilogram mass is thrown vertically upwardwith an initial speed of 9.80 meters per second.What is the maximum height this object willreach? [Neglect friction.]

A. 1.00 m B. 4.90 m

C. 9.80 m D. 19.6 m


Problem-Attic format version 4.4.312c_ 2011–2017 EducAide Software

Licensed for use by [email protected] of Use at www.problem-attic.com

Physics Midterm Review KEY 1/23/2018

1.Answer: A

2.Answer: A

3.Answer: C

4.Answer: B

5.Answer: C

6.Answer: B

7.Answer: C

8.Answer: C

9.Answer: D

10.Answer: B

11.Answer: D

12.Answer: B

13.Answer: D

14.Answer: D

15.Answer: A

16.Answer: D

17.Answer: A

18.Answer: B

19.Answer: C

20.Answer: C

21.Answer: P = (1.30 × 104N)(1.50m/s);

P = 1.95 × 104 W

22.Answer:

23.

Answer: ac =v2

r

ac =(12 m/s)2

50.mac = 2.9 m/s2 OR 2.8 m/s2

ac =v2

r

ac =(12 m/s)2

50.mac = 2.9 m/s2 OR 2.8 m/s2

24.Answer:

25.Answer: 1.96 N or 2.0 N or 1.9 N

26.Answer: Ff = µ FN

Ff = (0.36)(1.96 N)

Ff = 0.71 N or 0.70 N

Teacher’s Key Page 2

27.Answer: 3.3 N

28.Answer: the magnitude of the veolcity increases;

the block speeds up

29.Answer: A

30.Answer: B

31.Answer: A

32.Answer: D

33.Answer: D

34.Answer: A

35.Answer: C

36.Answer: C

37.Answer: A

38.Answer: B

39.Answer: B

40.Answer: B

41.Answer: A

42.Answer: D

43.Answer: C

44.Answer: B

45.Answer: C

46.Answer: D

47.Answer: 1.25 m/s2 ± 0.05 m/s2

48.

Answer: – d =

(5.0m/s + 10.0m/s

2

)4.0s

– d = 30.m

49.Answer: ac = 7.8 m/s2

50.Answer:

51.Answer: 120 J

52.Answer: 128 J

53.Answer: ∆PE = 120. J

54.Answer: The kinetic energy of the crate is

constant.

55.Answer: The internal energy of the crate increases.

56.Answer: B

57.Answer: C

58.Answer: A

59.Answer: D

60.Answer: D

61.Answer: A

62.Answer: B

63.Answer: D


64.Answer: A

65.Answer: A

66.Answer: D

67.Answer: C

68.Answer: A

69.Answer: A

70.Answer: C

71.Answer: C

72.Answer: D

73.Answer: D

74.Answer: B

75.Answer: D

76.Answer: B

77.Answer: A

78.Answer: D

79.Answer:

80.Answer:

81.Answer: D

82.Answer: A

83.Answer: The KE of the combined carts after the

collision is less than the KE of the cartsbefore the collision.

84.Answer: D

85.Answer: C

86.Answer: C

87.Answer: D

88.Answer: A

89.Answer: B

90.Answer: B

91.Answer: B

92.Answer: B

93.Answer: A

94.Answer: 800 J

95.Answer: work into or potential energy(spring) into

or kinetic energy into or potential energy(gravity)


96.Answer: The toy has less mass without the base

but the same energy. Therefore it can gohigher.

97.Answer: C

98.Answer: D

99.Answer: C

100.Answer: A

101.Answer: D

102.Answer: A

103.Answer: D

104.Answer: B

105.Answer: C

106.Answer: A

107.Answer: D

108.Answer: B

109.Answer: D

110.Answer: C

111.Answer: d = 6.0 m

112.Answer: d = 0.750 m

113.Answer: the measured times are the same

114.Answer: B

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Physics Midterm Review KEY Name: Date...A 0.0600-kilogram ball traveling at 60.0 meters per second hits a concrete wall. What speed must a 0.0100-kilogram bullet have in order to hit