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College Physics Chapter 6 Study Guide
Name__________________________
______ 1. If a particle’s kinetic energy is zero, what is its momentum?
a. zero
b. 1 kg• m/s
c. 15 kg• m/s
d. negative
______ 2. What is the momentum of a 0.148 kg baseball thrown with a velocity of 35 m/s toward home
plate?
a. 5.1 kgm/s toward home plate
b. 5.1 kgm/s away from home plate
c. 5.2 kgm/s away from home plate
d. 5.2 kgm/s toward home plate
Use the passage below to answer questions 3–4.
After being struck by a bowling ball, a 1.5 kg bowling pin slides to the right at 3.0 m/s and collides
head-on with another 1.5 kg bowling pin initially at rest.
______ 3. What is the final velocity of the second pin if the first pin moves to the right at 0.5 m/s after
the collision?
a. 2.5 m/s to the left b. 2.5 m/s to the right
c. 3.0 m/s to the left d. 3.0 m/s to the right
______ 4. What is the final velocity of the second pin if the first pin stops moving when it hits the second
pin?
a. 2.5 m/s to the left b. 2.5 m/s to the right
c. 3.0 m/s to the left d. 3.0 m/s to the right
______ 5. For a given change in momentum (constant), if the net force that is applied to an object
increases, what happens to the time interval over which the force is applied?
a. The time interval increases.
b. The time interval decreases.
c. The time interval stays the same.
______ 6. When comparing the momentum of two moving objects, which of the following is correct?
a. The object with the higher velocity will have less momentum if the masses are equal.
b. The more massive object will have less momentum if its velocity is greater.
c. The less massive object will have less momentum if the velocities are the same.
d. The more massive object will have less momentum if the velocities are the same.
______ 7. 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. Both the child and the bike have the same momentum.
b. The bike has a greater momentum than the child.
c. The child has a greater momentum than the bike.
d. Neither the child nor the bike has momentum.
______ 8. A roller coaster climbs up a hill at 4 m/s and then zips down the hill at 30 m/s. The momentum
of the roller coaster
a. is greater up the hill than down the hill.
b. is greater down the hill than up the hill.
c. remains the same throughout the ride.
d. is zero throughout the ride.
______9. 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. -4.0 kg•m/s
c. 0.0 kg•m/s
d. 8.0 kg•m/s
______10. The impulse experienced by a body is equivalent to the body’s change in
a. velocity.
b. kinetic energy
c. momentum.
d. force.
______11. A 75 kg person walking around a corner bumped into an 80 kg person who was running
around the same corner. The momentum of the 80 kg person
a. increased.
b. decreased.
c. remained the same.
d. was conserved.
______12. Two skaters stand facing each other. One skater’s mass is 60 kg, and the other’s mass is 72 kg.
If the skaters push away from each other without spinning,
a. the lighter skater has less momentum.
b. their momenta are equal but opposite.
c. their total momentum doubles.
d. their total momentum decreases.
______13. In a two-body collision,
a. momentum is always conserved.
b. kinetic energy is always conserved.
c. neither momentum nor kinetic energy is conserved.
d. both momentum and kinetic energy are always conserved.
______14. The law of conservation of momentum states that
a. the total initial momentum of all objects interacting with one another usually equals the total
final momentum.
b. the total initial momentum of all objects interacting with one another does not equal the total
final momentum.
c. the total momentum of all objects interacting with one another is zero.
d. the total momentum of all objects interacting with one another remains constant regardless
of the nature of the forces between the objects.
______15. What is the product of an object’s mass and its velocity?
a. kinetic energy
b. momentum
c. impulse
d. inertia
______16. Which of the following has the greatest momentum?
a. a 4.0 kg bowling ball moving at 2.0 m/s
b. a 0.15 kg baseball moving at 10.0 m/s
c. a 1.6 x 103 kg car moving at 0.5 m/s
d. a 0.02 kg bullet moving at 950 m/s
______17. How does the momentum of an object change if the object’s velocity doubles?
a. The momentum doubles.
b. The momentum increases by a factor of four.
c. The momentum decreases by a factor of 1/2.
d. The momentum decreases by a factor of 1/4.
______18. What are the units of momentum?
a. N
b. J
c. kg•m/s
d. kg•m/s2
______19. Which of the following can determine the magnitude of the change in an object’s momentum?
a. mass and acceleration
b. force and time interval
c. force and distance
d. acceleration and time interval
______20. Which of the following is true of changes in momentum?
a. A small force may produce a large change in momentum by acting over a short time
interval.
b. A small force may produce a large change in momentum by acting over a large time.
c. A large force may produce a large change in momentum by acting over a large time.
d. A large force may produce a small change in momentum by acting over a short time
interval.
______21. If a net force acts on an object, then the object’s momentum
a. will increase. b. will decrease. c. will either increase or decrease.
d. may or may not change.
______22. Which of the following involves a change in momentum?
a. A bowling ball rolls down the lane at constant speed.
b. A car coasts down a hill at constant speed.
c. A sky diver descends with terminal velocity.
d. A spacecraft travels at constant speed while slowly losing mass.
______23. A batter hits a baseball back to the pitcher at the same speed as the pitch. Which of the
following is true?
a. The momentum of the ball is the same before and after the batter hits the ball.
b. The magnitude of the ball’s momentum is greater after the batter hits the ball.
c. The magnitude of the ball’s momentum is less after the batter hits the ball.
d. The magnitude of the ball’s momentum is the same before and after the batter hits the ball.
______24. A small marble collides with a billiard ball that is initially at rest. Which of the following is
true?
a. The momentum of each object increases.
b. The momentum of each object decreases.
c. The momentum of the billiard ball increases, and the momentum of the marble decreases.
d. The total momentum before and after the collision is zero.
______25. When two ice skaters initially at rest push off one another, their final momenta are
a. equal in magnitude and direction.
b. equal in magnitude and opposite in direction.
c. in the same direction but of different magnitudes
d. in opposite directions and possibly of different magnitudes.
______26. When two objects interact in an isolated system,
a. the momentum of each object is conserved.
b. the total momentum of the system is zero.
c. the total momentum is conserved only if the objects move in opposite directions.
d. the total momentum is always conserved.
______27. Which of the following expresses the law of conservation of momentum?
a. The total momentum of an isolated system is zero.
b. The total momentum of any system always remains constant.
c. Every object in an isolated system maintains a constant momentum.
d. The total momentum of an isolated system remains constant regardless of the forces
between the objects in the system.
______28. Conservation of momentum follows from
a. Newton’s first law.
b. Newton’s second law. c. Newton’s third law.
______29. A billiard ball hits the edge of another billiard ball that is initially at rest. The second ball
moves off at an angle. Which of the following is true?
a. The momentum of the first ball doesn’t change.
b. The momentum of the second ball doesn’t change.
c. The total momentum of the system increases.
d. The momentum lost by the first ball is gained by the second ball.
______30. A croquet ball moving at 2.0 m/s strikes another ball of equal mass. The first ball stops
moving after the collision. What is the velocity of the second ball after the collision?
a. -2.0 m/s
b. 0 m/s
c. 2.0 m/s
d. 4.0 m/s
______31. Two cars collide, lock bumpers, and move together after the collision. What kind of collision
is this?
a. elastic collision
b. inelastic collision c. perfectly elastic collision d. perfectly inelastic collision
______32. A tennis ball is dropped from 1.0 m, bounces off the ground, and rises to 0.85 m. What kind of
collision occurred between the ball and the ground?
a. elastic collision
b. inelastic collision c. perfectly elastic collision d. perfectly inelastic collision
______33. In what kind of collision is kinetic energy always conserved?
a. elastic collision
b. inelastic collision c. perfectly elastic collision
d. perfectly inelastic collision
______34. Most collisions in the everyday world are
a. elastic collision
b. inelastic collision c. perfectly elastic collision
d. perfectly inelastic collision
______35. A helium atom collides with another helium atom in an elastic collision. Which of the
following is true?
a. Both momentum and kinetic energy are conserved.
b. Momentum is conserved but kinetic energy is not conserved.
c. Kinetic energy is conserved but momentum is not conserved.
d. Neither momentum nor kinetic energy is conserved.
______36. Two playground balls collide in an inelastic collision. Which of the following is true?
a. Both momentum and kinetic energy are conserved.
b. Momentum is conserved, but kinetic energy is not conserved.
c. Kinetic energy is conserved, but momentum is not conserved.
d. Neither momentum nor kinetic energy is conserved.
______37. Which of the following is not evidence that kinetic energy has been lost in a collision?
a. The collision produces a sound.
b. At least one of the objects is deformed after the collision.
c. At least one of the objects increases in temperature as a result of the collision.
d. One of the objects is at rest after the collision.
________38. Two objects move separately after colliding, and both the total momentum and
total kinetic energy remain constant. Identify the type of collision.
a. elastic collision
b. inelastic collision c. perfectly elastic collision d. perfectly inelastic collision
________39. Two objects stick together and move with a common velocity after colliding.
Identify the type of collision.
a. elastic collision
b. inelastic collision c. perfectly elastic collision d. perfectly inelastic collision
________40. After colliding, objects are deformed and lose some kinetic energy. Identify the
type of collision.
a. elastic collision
b. inelastic collision c. perfectly elastic collision d. perfectly inelastic collision