1.
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Two men, Joel and Jerry, push against a wall. Jerry stops after 10 min, while Joel is able to push for 5 min longer. Compare the work against the wall they each do.
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| Joel does 50% more work than Jerry. |
| Jerry does 50% more work than Joel. |
| Joel does 75% more work than Jerry. |
| Neither of them do any work. |
|
2.
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Which of the following graphs illustrates Hooke's Law (the spring force)?
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|  |
|  |
|  |
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3.
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 A simple pendulum, consisting of a mass m and a string, swings upward, making an angle q with the vertical. The work done by the tension force is
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| zero. |
| mg. |
| mg cos q. |
| mg sin q. |
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4.
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Vector A is of length 2 and is 30o north of east and vector B is of length 1 and pointed due north. The scalar product of the two vectors is
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| 0.5 |
| 1.0 |
| 1.7 |
| 2 |
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5.
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Vector A=2i+3j+0k and Vector B=2i-3j+0k, the dot product of the two vectors is
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| -5 |
| 0 |
| 5 |
| 13 |
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6.
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Vector A=2i+3j+1k and B=2i-3j+5k, the dot product of the two vectors is
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| -5 |
| 0 |
| 5 |
| 14 |
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7.
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A 4-kg mass moving with speed 2 m/s, and a 2-kg mass moving with a speed of 4 m/s, are gliding over a horizontal frictionless surface. Both objects encounter the same horizontal force, which directly opposes their motion, and are brought to rest by it. Which statement best describes their respective stopping distances?
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| The 4-kg mass travels twice as far as the 2-kg mass before stopping. |
| The 2-kg mass travels twice as far as the 4-kg mass before stopping. |
| Both masses travel the same distance before stopping. |
| The 2 kg mass travels greater than twice as far. |
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8.
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A 4-kg mass moving with speed 2 m/s and, an otherwise identical, 2-kg mass moving with a speed of 4 m/s, are gliding over a horizontal surface with friction and are brought to rest by it. Which statement best describes their respective stopping distances?
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| The 4-kg mass travels twice as far as the 2-kg mass before stopping. |
| The 2-kg mass travels twice as far as the 4-kg mass before stopping. |
| Both masses travel the same distance before stopping. |
| The 2-kg mass travels greater than twice as far. |
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9.
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A force that object A exerts on object B is observed over a 10-second interval, as shown on the graph. How much work did object A do during that 10 s?
|
| Zero |
| 12.5 J |
| 25 J |
| 50 J |
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10.
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The resultant force you exert on a shopping cart, for a 10 s period, is plotted on the graph, shown. How much work did you do during this 10 s interval?
|
| Zero |
| 12.5 J |
| 25 J |
| -25 J |
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11.
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What was the total work done on you by all the forces in the universe between the time just before you awoke this morning and right now?
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| Don't have a clue. |
| Greater than zero. |
| Zero. |
| Can not be calculated. |
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12.
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The work done by friction, f,
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| equals -fd, where d is the total distance moved. |
| equals fd, where d is the total distance. |
| can't easily be calculated because it depends on the angle between f and d. |
| can't easily be calculated. |
|
13.
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A 102 kg man climbs a 5.0 meter high stair case at constant speed How much work does he do?
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| 510 J |
| 49 J |
| 5000 J |
| 2500 J |
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14.
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A 2 kg mass travelling at 1.8 m/s has a kinetic energy of
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| 3.24 J |
| 5 J |
| 6.48 J |
| 10 J |
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15.
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A 2 kg mass traveling at 1.8x108 m/s has a kinetic energy of
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| 4.5x1016 J |
| 3.5x1016 J |
| 2.5x1016 J |
| none of the above |
