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2. QuickCheck 6.1
A hollow tube lies flat on a table. A ball is shot through the tube. As the ball emerges from the other end, which path does it follow?
Answer: C
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3. QuickCheck 6.1 C C
A hollow tube lies flat on a table. A ball is shot through the tube. As the ball emerges from the other end, which path does it follow?
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4. QuickCheck 6.2
A ball at the end of a string is being swung in a horizontal circle. The ball is accelerating because
The speed is changing.
The direction is changing.
The speed and the direction are changing.
The ball is not accelerating.
Answer: B
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5. QuickCheck 6.2
A ball at the end of a string is being swung in a horizontal circle. The ball is accelerating because
The speed is changing.
The direction is changing.
The speed and the direction are changing.
The ball is not accelerating.
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6. QuickCheck 6.3
A ball at the end of a string is being swung in a horizontal circle. What is the direction of the acceleration of the ball?
Tangent to the circle, in the direction of the ball’s motion
Toward the center of the circle
Answer: B
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7. QuickCheck 6.3
A ball at the end of a string is being swung in a horizontal circle. What is the direction of the acceleration of the ball?
Tangent to the circle, in the direction of the ball’s motion
Toward the center of the circle
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8. QuickCheck 6.4
A ball at the end of a string is being swung in a horizontal circle. What force is producing the centripetal acceleration of the ball?
Gravity
Air resistance
Normal force
Tension in the string
Answer: D
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9. QuickCheck 6.4
A ball at the end of a string is being swung in a horizontal circle. What force is producing the centripetal acceleration of the ball?
Gravity
Air resistance
Normal force
Tension in the string
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10. QuickCheck 6.5
A ball at the end of a string is being swung in a horizontal circle. What is the direction of the net force on the ball?
Tangent to the circle
Toward the center of the circle
There is no net force.
Answer: B
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11. QuickCheck 6.5
A ball at the end of a string is being swung in a horizontal circle. What is the direction of the net force on the ball?
Tangent to the circle
Toward the center of the circle
There is no net force.
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12. QuickCheck 6.6
An ice hockey puck is tied by a string to a stake in the ice. The puck is then swung in a circle. What force is producing the centripetal acceleration of the puck?
Gravity
Air resistance
Friction
Normal force
Tension in the string
Answer: E
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13. QuickCheck 6.6
An ice hockey puck is tied by a string to a stake in the ice. The puck is then swung in a circle. What force is producing the centripetal acceleration of the puck?
Gravity
Air resistance
Friction
Normal force
Tension in the string
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14. QuickCheck 6.7
A coin is rotating on a turntable; it moves without sliding. At the instant shown in the figure, which arrow gives the direction of the coin’s velocity?
Answer: A
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15. QuickCheck 6.7
A coin is rotating on a turntable; it moves without sliding. At the instant shown in the figure, which arrow gives the direction of the coin’s velocity? A
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16. QuickCheck 6.8
A coin is rotating on a turntable; it moves without sliding. At the instant shown in the figure, which arrow gives the direction of the frictional force on the coin?
Answer: D
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17. QuickCheck 6.8
A coin is rotating on a turntable; it moves without sliding. At the instant shown in the figure, which arrow gives the direction of the frictional force on the coin? D
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18. QuickCheck 6.9
A coin is rotating on a turntable; it moves without sliding. At the instant shown, suppose the frictional force disappeared. In what direction would the coin move?
Answer: A
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19. QuickCheck 6.9
A coin is rotating on a turntable; it moves without sliding. At the instant shown, suppose the frictional force disappeared. In what direction would the coin move? A
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20. QuickCheck 6.10
A physics textbook swings back and forth as a pendulum. Which is the correct free-body diagram when the book is at the bottom and moving to the right?
Answer: C
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21. QuickCheck 6.10
A physics textbook swings back and forth as a pendulum. Which is the correct free-body diagram when the book is at the bottom and moving to the right?
Centripetal acceleration requires an upward force. C.
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22. QuickCheck 6.11
A car that’s out of gas coasts over the top of a hill at a steady 20 m/s. Assume air resistance is negligible. Which free-body diagram describes the car at this instant?
Answer: A
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23. QuickCheck 6.11
A car that’s out of gas coasts over the top of a hill at a steady 20 m/s. Assume air resistance is negligible. Which free-body diagram describes the car at this instant?
Now the centripetal acceleration points down. A.
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24. QuickCheck 6.12
A roller coaster car does a loop-the-loop. Which of the free- body diagrams shows the forces on the car at the top of the loop? Rolling friction can be neglected.
Answer: E
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25. QuickCheck 6.12
A roller coaster car does a loop-the-loop. Which of the free- body diagrams shows the forces on the car at the top of the loop? Rolling friction can be neglected.
The track is above the car, so the normal force of the track pushes down. E.
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26. QuickCheck 6.13
A coin sits on a turntable as the table steadily rotates counterclockwise. What force or forces act in the plane of the turntable?
Answer: A
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27. QuickCheck 6.13
A coin sits on a turntable as the table steadily rotates counterclockwise. What force or forces act in the plane of the turntable? A.
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28. QuickCheck 6.14
A coin sits on a turntable as the table steadily rotates counterclockwise. The free-body diagrams below show the coin from behind, moving away from you. Which is the correct diagram?
Answer: C
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29. QuickCheck 6.14
A coin sits on a turntable as the table steadily rotates counterclockwise. The free-body diagrams below show the coin from behind, moving away from you. Which is the correct diagram? C.
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30. QuickCheck 6.15
A car turns a corner on a banked road. Which of the diagrams could be the car’s free-body diagram?
Answer: E
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31. QuickCheck 6.15
A car turns a corner on a banked road. Which of the diagrams could be the car’s free-body diagram? E.
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32. QuickCheck 6.16
The force of Planet Y on Planet X is ___ the magnitude of
One quarter
One half
The same as
Twice
Four times 2M M
Answer: C
Planet X
Planet Y
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33. QuickCheck 6.16
The force of Planet Y on Planet X is ___ the magnitude of
One quarter
One half
The same as
Twice
Four times 2M M
Newton’s third law
Planet X
Planet Y
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34. QuickCheck 6.17
The gravitational force between two asteroids is 1,000,000 N. What will the force be if the distance between the asteroids is doubled?
250,000 N
500,000 N
1,000,000 N
2,000,000 N
4,000,000 N
Answer: A
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35. QuickCheck 6.17
The gravitational force between two asteroids is 1,000,000 N. What will the force be if the distance between the asteroids is doubled?
250,000 N
500,000 N
1,000,000 N
2,000,000 N
4,000,000 N
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36. QuickCheck 6.18
Planet X has free-fall acceleration 8 m/s2 at the surface. Planet Y has twice the mass and twice the radius of planet X. On Planet Y
g = 2 m/s2
g = 4 m/s2
g = 8 m/s2
g = 16 m/s2
g = 32 m/s2
Answer: B
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37. QuickCheck 6.18
Planet X has free-fall acceleration 8 m/s2 at the surface. Planet Y has twice the mass and twice the radius of planet X. On Planet Y
g = 2 m/s2
g = 4 m/s2
g = 8 m/s2
g = 16 m/s2
g = 32 m/s2
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38. QuickCheck 6.19
Astronauts on the International Space Station are weightless because
There’s no gravity in outer space.
The net force on them is zero.
The centrifugal force balances the gravitational force.
g is very small, although not zero.
They are in free fall.
Answer: E
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39. QuickCheck 6.19
Astronauts on the International Space Station are weightless because
There’s no gravity in outer space.
The net force on them is zero.
The centrifugal force balances the gravitational force.
g is very small, although not zero.
They are in free fall.
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40. QuickCheck 6.20
Two satellites have circular orbits with the same radius. Which has a higher speed?
The one with more mass.
The one with less mass.
They have the same speed.
Answer: C
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41. QuickCheck 6.20
Two satellites have circular orbits with the same radius. Which has a higher speed?
The one with more mass.
The one with less mass.
They have the same speed.
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42. QuickCheck 6.21
Two identical satellites have different circular orbits. Which has a higher speed?
The one in the larger orbit
The one in the smaller orbit
They have the same speed.
Answer: B
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43. QuickCheck 6.21
Two identical satellites have different circular orbits. Which has a higher speed?
The one in the larger orbit
The one in the smaller orbit
They have the same speed.
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44. QuickCheck 6.22
A 60-kg person stands on each of the following planets. On which planet is his or her weight the greatest?
Answer: A
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45. QuickCheck 6.22
A 60-kg person stands on each of the following planets. On which planet is his or her weight the greatest? A
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46. QuickCheck 6.23
A satellite orbits the earth. A Space Shuttle crew is sent to boost the satellite into a higher orbit. Which of these quantities increases?
Speed
Angular speed
Period
Centripetal acceleration
Gravitational force of the earth
Answer: C
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47. QuickCheck 6.23
A satellite orbits the earth. A Space Shuttle crew is sent to boost the satellite into a higher orbit. Which of these quantities increases?
Speed
Angular speed
Period
Centripetal acceleration
Gravitational force of the earth
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