Question 1

If you want to double the momentum of a gas molecule, by what factor must you increase its kinetic energy?

Accepted Answer

A)  2 
B)  4 
C)  $2 \sqrt { 2 }$ 
D)  $\sqrt { 2 }$ 
E)  16 
A)  2 
B)  4 
C)  $2 \sqrt { 2 }$ 
D)  $\sqrt { 2 }$ 
E)  16

Question 2

A dinner plate falls vertically to the floor and breaks up into three pieces, which slide horizontally along the floor. Immediately after the impact, a 200-g piece moves along the  +x -axis with a speed of  2.00 m/s, a  235-g piece moves along the  +y -axis with a speed of  1.50 m/s. The third piece has a mass of  100 g. What is the speed of the third piece?

Accepted Answer

A)   2.57 m/s 
B)   6.83 m/s 
C)   5.33 m/s 
D)   3.50 m/s 
E)   2.51 m/s 
A)   2.57 m/s 
B)   6.83 m/s 
C)   5.33 m/s 
D)   3.50 m/s 
E)   2.51 m/s

Question 3

A golf ball of mass  0.050 kg is at rest on the tee. Just after being struck, it has a velocity of  102 m/s. If the club and ball were in contact for  0.81 ms, what is the average force exerted on the ball by the club?

Accepted Answer

A)   5.5 kN 
B)   4.9 kN 
C)   7.1 kN 
D)   6.3 kN 
A)   5.5 kN 
B)   4.9 kN 
C)   7.1 kN 
D)   6.3 kN

Question 4

Two dogs, Rover and Fido, run on a level frictionless surface. Rover runs eastward with a momentum of $24 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ and Fido runs northward with momentum $10 \mathrm {~kg} , \mathrm {~m} / \mathrm { s }$ They make a sudden perfectly inelastic collision. What is the magnitude of their combined momentum after the collision?

Accepted Answer

A)  $34 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
B)  $26 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
C)  $14 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
D)  It cannot be determined without knowing the masses and velocities of the dogs. 
A)  $34 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
B)  $26 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
C)  $14 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
D)  It cannot be determined without knowing the masses and velocities of the dogs.

Question 5

Two air track carts move along an air track towards each other. Cart A has a mass of  450 g and moves toward the right with a speed of  0.850 m/s. Cart B has a mass of  300 g and moves toward the left with a speed of  1.12 m/s. What is the total momentum of the two-cart system?

Accepted Answer

A)   0.047 kg . m/s toward the right 
B)   0.750 kg . m/s toward the right 
C)   0.750 kg . m/s toward the left 
D)   0.719 kg . m/s toward the right 
E)   0.719 kg . m/s toward the left 
A)   0.047 kg . m/s toward the right 
B)   0.750 kg . m/s toward the right 
C)   0.750 kg . m/s toward the left 
D)   0.719 kg . m/s toward the right 
E)   0.719 kg . m/s toward the left

Question 6

A very small  51-g steel ball is released from rest and falls vertically onto a steel plate. The ball strikes the plate and is in contact with it for  0.50 ms. The ball rebounds elastically and returns to its original height. The total time interval for a round trip is  3.00 s. What is the magnitude of the average force exerted on the ball by the plate during contact with the plate?

Accepted Answer

A)   2490 N 
B)   1500 N 
C)   3000 N 
D)   2000 N 
E)   3500 N 
A)   2490 N 
B)   1500 N 
C)   3000 N 
D)   2000 N 
E)   3500 N

Question 7

A 900-kg car traveling east at  15.0 m/s suddenly collides with a  750-kg car traveling north at  20.0 m/s . The cars stick together after the collision. What is the speed of the wreckage just after the collision?

Accepted Answer

A)   35.0 m/s 
B)   17.3 m/s 
C)   25.0 m/s 
D)   12.2 m/s 
E)   6.10 m/s 
A)   35.0 m/s 
B)   17.3 m/s 
C)   25.0 m/s 
D)   12.2 m/s 
E)   6.10 m/s

Question 8

A golf club exerts an average horizontal force of 1000 N on a 0.045-kg golf ball that is initially at rest on the tee. The club is in contact with the ball for 1.8 ms. What is the speed of the golf ball just
As it leaves the tee?

Accepted Answer

A)  40 m/s 
B)  45 m/s 
C)  30 m/s 
D)  35 m/s 
E)  50 m/s 
A)  40 m/s 
B)  45 m/s 
C)  30 m/s 
D)  35 m/s 
E)  50 m/s

Question 9

What is the magnitude of the momentum of a 0.140 kg baseball traveling at 45.0 m/s?

Accepted Answer

The answer of What is the magnitude of the momentum...

Question 10

A  2.0-kg ball moving eastward at  3.0 m/s suddenly collides with and sticks to a  4.0-kg ball moving northward at  2.0 m/s. What is the magnitude of the momentum of this system just after the collision?

Accepted Answer

A)  $6.0 \mathrm{~kg}=\mathrm{m} / \mathrm{s}$ 
B)  $8.0 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
C)  $10 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
D)  $14 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
E)  $2.0 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
A)  $6.0 \mathrm{~kg}=\mathrm{m} / \mathrm{s}$ 
B)  $8.0 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
C)  $10 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
D)  $14 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
E)  $2.0 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$

Question 11

A super dart of mass  20 g, traveling at  350 m/s, strikes a steel plate at an angle of $30 ^ { \circ }$ with the plane of the plate, as shown in the figure. It bounces off the plate at the same angle but at a speed of 320  m/s. What is the magnitude of the impulse that the plate gives to the bullet?

Accepted Answer

A)  $4.3 \mathrm {~N} \cdot \mathrm { s }$ 
B)  $300 \mathrm {~N} \cdot \mathrm { s }$ 
C)  $0.30 \mathrm {~N} \cdot \mathrm { s }$ 
D)  $6.7 \mathrm {~N} \cdot \mathrm { s }$ 
E)  $0.52 \mathrm {~N} \cdot \mathrm { s }$ 
A)  $4.3 \mathrm {~N} \cdot \mathrm { s }$ 
B)  $300 \mathrm {~N} \cdot \mathrm { s }$ 
C)  $0.30 \mathrm {~N} \cdot \mathrm { s }$ 
D)  $6.7 \mathrm {~N} \cdot \mathrm { s }$ 
E)  $0.52 \mathrm {~N} \cdot \mathrm { s }$

Question 12

A  320-g air track cart traveling at  1.25 m/s  suddenly collides elastically with a stationary  270-g cart. What is the speed of the  320-g cart just after the collision?

Accepted Answer

A)   1.1 m/s 
B)   0.21 m/s 
C)   0.68 m/s 
D)   0.11 m/s 
E)   1.4 m/s 
A)   1.1 m/s 
B)   0.21 m/s 
C)   0.68 m/s 
D)   0.11 m/s 
E)   1.4 m/s

Question 13

Three objects are moving along a straight line as shown in the figure. Taking the positive direction to be to the right, what is the total momentum of this system?

Accepted Answer

A)  $- 14.0 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
B)  $+ 14.0 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
C)  $+ 106 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
D)  $0.00 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
E)  $- 106 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
A)  $- 14.0 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
B)  $+ 14.0 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
C)  $+ 106 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
D)  $0.00 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
E)  $- 106 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$

Question 14

A $1500 - \mathrm { kg }$ car traveling at $90 \mathrm {~km} / \mathrm { h }$ toward the east suddenly collides with a $3000 - \mathrm { kg }$ car traveling at $60 \mathrm {~km} / \mathrm { h }$ toward the south. The two cars stick together after the collision. What is the speed of the cars after collision?

Accepted Answer

A)  14 m/s 
B)  17 m/s 
C)  22 m/s 
D)  8.3 m/s 
A)  14 m/s 
B)  17 m/s 
C)  22 m/s 
D)  8.3 m/s

Question 15

In an inelastic collision involving an isolated system, the final total momentum is

Accepted Answer

A)  more than the initial momentum. 
B)  less than the initial momentum. 
C)  exactly the same as the initial momentum. 
A)  more than the initial momentum. 
B)  less than the initial momentum. 
C)  exactly the same as the initial momentum.

Question 16

A 2.0-kg mass moving at 5.0 m/s suddenly collides head-on with a 3.0-kg mass at rest. If the collision is perfectly inelastic, what is the speed of the masses just after the collision?

Accepted Answer

A)  2.0 m/s 
B)  10 m/s 
C)  2.5 m/s 
D)  0 m/s, since the collision is inelastic 
A)  2.0 m/s 
B)  10 m/s 
C)  2.5 m/s 
D)  0 m/s, since the collision is inelastic

Question 17

Two objects of different masses have momentum of equal, non-zero magnitude. Which object has more kinetic energy?

Accepted Answer

A)  the lighter object 
B)  the heavier object 
C)  They both have the same kinetic energy. 
A)  the lighter object 
B)  the heavier object 
C)  They both have the same kinetic energy.

Question 18

A 5-kg ball collides inelastically head-on with a  10-kg ball, which is initially stationary. Which of the following statements is true? (There could be more than one correct choice.)

Accepted Answer

A)  The magnitude of the change of the momentum of the  5-kg  ball is equal to the magnitude of the change of momentum of the  10-kg ball. 
B)  The magnitude of the change of velocity the 5-kg ball experiences is greater than that of the 10-kg ball. 
C)  Both balls lose all their momentum since the collision is inelastic. 
D)  The magnitude of the change of velocity the 5-kg ball experiences is equal to that of the 10-kg ball. 
E)  The magnitude of the change of velocity the 5-kg ball experiences is less than that of the 10-kg ball. 
A)  The magnitude of the change of the momentum of the  5-kg  ball is equal to the magnitude of the change of momentum of the  10-kg ball. 
B)  The magnitude of the change of velocity the 5-kg ball experiences is greater than that of the 10-kg ball. 
C)  Both balls lose all their momentum since the collision is inelastic. 
D)  The magnitude of the change of velocity the 5-kg ball experiences is equal to that of the 10-kg ball. 
E)  The magnitude of the change of velocity the 5-kg ball experiences is less than that of the 10-kg ball.

Question 19

A  0.10-kg ball, traveling horizontally at  25 m/s, strikes a wall and rebounds at  19 m/s. What is the magnitude of the change in the momentum of the ball during the rebound?

Accepted Answer

A)  $5.4 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
B)  $1.8 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
C)  $4.4 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
D)  $1.2 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
E)  $72 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
A)  $5.4 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
B)  $1.8 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
C)  $4.4 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
D)  $1.2 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$ 
E)  $72 \mathrm {~kg} \cdot \mathrm { m } / \mathrm { s }$

Question 20

A 340-g air track cart traveling at  1.25 m/s suddenly collides elastically with a stationary  300-g  cart. What is the speed of the  300-g cart just after the collision?

Accepted Answer

A)   0.625 m/s 
B)   0.0781 m/s 
C)   1.25 m/s 
D)   0.664 m/s 
E)   1.33 m/s 
A)   0.625 m/s 
B)   0.0781 m/s 
C)   1.25 m/s 
D)   0.664 m/s 
E)   1.33 m/s

Exam 7: Linear Momentum

If you want to double the momentum of a gas molecule, by what factor must you increase its kinetic energy?

A golf ball of mass 0.050 kg is at rest on the tee. Just after being struck, it has a velocity of 102 m/s. If the club and ball were in contact for 0.81 ms, what is the average force exerted on the ball by the club?

Two air track carts move along an air track towards each other. Cart A has a mass of 450 g and moves toward the right with a speed of 0.850 m/s. Cart B has a mass of 300 g and moves toward the left with a speed of 1.12 m/s. What is the total momentum of the two-cart system?

A 900-kg car traveling east at 15.0 m/s suddenly collides with a 750-kg car traveling north at 20.0 m/s . The cars stick together after the collision. What is the speed of the wreckage just after the collision?

A golf club exerts an average horizontal force of 1000 N on a 0.045-kg golf ball that is initially at rest on the tee. The club is in contact with the ball for 1.8 ms. What is the speed of the golf ball just As it leaves the tee?

What is the magnitude of the momentum of a 0.140 kg baseball traveling at 45.0 m/s?

A 2.0-kg ball moving eastward at 3.0 m/s suddenly collides with and sticks to a 4.0-kg ball moving northward at 2.0 m/s. What is the magnitude of the momentum of this system just after the collision?

A 320-g air track cart traveling at 1.25 m/s suddenly collides elastically with a stationary 270-g cart. What is the speed of the 320-g cart just after the collision?

Three objects are moving along a straight line as shown in the figure. Taking the positive direction to be to the right, what is the total momentum of this system?

In an inelastic collision involving an isolated system, the final total momentum is

A 2.0-kg mass moving at 5.0 m/s suddenly collides head-on with a 3.0-kg mass at rest. If the collision is perfectly inelastic, what is the speed of the masses just after the collision?

Two objects of different masses have momentum of equal, non-zero magnitude. Which object has more kinetic energy?

A 5-kg ball collides inelastically head-on with a 10-kg ball, which is initially stationary. Which of the following statements is true? (There could be more than one correct choice.)

A 0.10-kg ball, traveling horizontally at 25 m/s, strikes a wall and rebounds at 19 m/s. What is the magnitude of the change in the momentum of the ball during the rebound?

A 340-g air track cart traveling at 1.25 m/s suddenly collides elastically with a stationary 300-g cart. What is the speed of the 300-g cart just after the collision?

Introduction, Measurement, Estimating

Describing Motion: Kinematics in One Dimension

Kinematics in Two Dimensions; Vectors

Dynamics: Newtons Laws of Motion

Circular Motion; Gravitation

Work and Energy

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Static Equilibrium; Elasticity and Fracture

Fluids

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Temperature and Kinetic Theory

Heat

The Laws of Thermodynamics

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Electric Potential

Electric Currents

Dc Circuits

Magnetism

Electromagnetic Induction and Faradays Law

Electromagnetic Waves

Light: Geometric Optics

The Wave Nature of Light

Optical Instruments

The Special Theory of Relativity

Early Quantum Theory and Models of the Atom

Quantum Mechanics of Atoms

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Nuclear Energy; Effects and Uses of Radiation

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