1.
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A puck resting on an air hockey table is attached to a string and given an initial tangential push such that it travels in a circle at constant speed. What is the magnitude of the acceleration of the puck? (Position is in meters and time is in seconds.) Start
Interactive Hint
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| zero, because the puck moves at constant speed |
| 0.94 m/s2 |
| 1.5 m/s2 |
| 4.0 m/s2 |
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2.
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A 1 kg mass moves in a circle as shown. Which vector represents the net force on the object? Start
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| The blue vector |
| The green vector |
| The black vector |
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3.
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A 0.25 kg puck resting on an air hockey table is attached to a string and given an initial tangential push such that it travels in a circle at constant speed. The string is attached to a screw in the middle of the table. What is the force of the string on the screw at t=3 s? (Position is in meters and time is in seconds.)Start
Interactive Hint
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| zero, because the puck moves at constant speed |
| 2.45 N downward |
| 0.37 N upward |
| 0.37 N downward |
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4.
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A Ferris wheel rotates at constant speed as shown in the animation. Each square represents a chair on the Ferris wheel. What applied forces act on a rider when the rider is at point (a), (x,y) = (0,-6)? Start
Interactive Hint
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| Normal force upward, weight downward. |
| Normal force upward, weight downward, centripetal force upward. Review Section 5-2 in Giancoli. |
| Normal force upward, weight downward, centripetal force downward. |
| Normal force downward, weight downward, centripetal force upward. |
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5.
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A coin rests on a turntable which is slowing down. Identify the tangential component of the coin's acceleration at t=2 seconds.Start
Interactive Hint
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| In the direction of the green vector. |
| In the direction of the purple vector. |
| In the direction of the orange vector. |
| In the direction of the red vector. |
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6.
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A car starts from rest and accelerates until it is half way around a circular track after which time it moves at constant speed. Which animation correctly shows the acceleration vector?
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| Animation a: |
| Animation b: |
| Animation c: |
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7.
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A space station travels around the Earth in a circular orbit as shown in the animation. What is the magnitude of the acceleration of the space station in terms of g (9.8 m/s2)? Position is shown in units of 106 m and time shown is in hours. Start
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| zero, since the astronauts are feel weightless |
| g |
| 0.56g |
| 0.28g |
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8.
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A 5000 kg space station travels around the Earth in a circular orbit as shown in the animation. What is the magnitude of the gravitational force of the space station on the Earth? Position is shown in units of 106 m and time shown is in hours. Start
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| Zero, since the mass of the space station is so small compared to the mass of the Earth. |
| Zero, since the Earth attracts the space station with a much greater force. |
| 27,440 N |
| 13,720 N |
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9.
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Two satellites of equal mass, Satellite 1 and Satellite 2, orbit concentrically about the Earth as shown in the animation. What is the ratio of the gravitational force on Satellite 1 to the gravitational force on Satellite 2 (i.e. F1/F2)? Position is in units of 106 m and time is in hours. Start
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| 0.56 |
| 0.75 |
| 1 |
| 1.78 |
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10.
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A planet orbits a star as shown in the animation. What is the mass of the star? Position is in units of 108 m and time is in hours. Start
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| 2 x 1030 kg |
| 5 x 1030 kg |
| 8.65 x 1031 kg |
| 8.65 x 1025 kg |
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11.
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The animation purports to model a solar system, however one of the planets does not obey all of Kepler's laws. Identify that planet. (The sun is yellow.) Start
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| green |
| blue |
| black |
| red |
