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| 1 | In the absence of friction, air resistance, or other dissipative forces, the total kinetic energy remains constant. |
 | A) | True |
| B) | False |
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| 2 | The total energy of a system of bodies in isolation may be defined as the sum of the individual kinetic and potential energies. |
| A) | True |
| B) | False |
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| 3 | All moving bodies possess kinetic energy. |
| A) | True |
| B) | False |
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| 4 | The work of a resultant force on a body is equal to the change in kinetic energy. |
| A) | True |
| B) | False |
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| 5 | As a body falls, its potential energy increases with its speed. |
| A) | True |
| B) | False |
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| 6 | A 1-hp engine will do work at a faster rate than a 1-kW engine. |
| A) | True |
| B) | False |
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| 7 | The kilowatthour is a unit of energy. |
| A) | True |
| B) | False |
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| 8 | As an object falls freely from the top of a building, its total energy remains constant. |
| A) | True |
| B) | False |
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| 9 | If we consider friction, the potential energy at the top of an inclined plane is less than it would be in the absence of friction. |
| A) | True |
| B) | False |
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| 10 | According to convention, negative work means that the direction of the work is downward or to the left. |
| A) | True |
| B) | False |
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| 11 | Which of the following is not necessary for work to be done? |
| A) | An applied force |
| B) | A force component along the displacement |
| C) | A displacement |
| D) | A constant speed |
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| 12 | Which of the following is not a unit of work or energy? |
| A) | Newton-meter |
| B) | Joule |
| C) | Foot-pound per second |
| D) | Kilowatthour |
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| 13 | The largest unit of power is the |
| A) | kilowatt |
| B) | watt |
| C) | foot-pound per second |
| D) | horsepower |
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| 14 | A force of 20 N moves a 10-kg block through a distance of 400 cm. The work done by the 20-N force is |
| A) | 8000 J |
| B) | 80,000 J |
| C) | 80 J |
| D) | 80 N * m |
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| 15 | A 10-kg block is lifted 20 m above the ground in a gravitational field. The work done by the field is |
| A) | negative |
| B) | positive |
| C) | equal to the final potential energy |
| D) | a vector quantity |
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| 16 | In Question 15, the gravitational potential energy of the block after it has been lifted 20 m is |
| A) | 196 J |
| B) | 1960 J |
| C) | -1960 J |
| D) | 200 J |
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| 17 | A 1-hp motor will lift a 200-lb block to what height in 2 s? |
| A) | 0.01 ft |
| B) | 0.727 ft |
| C) | 100 ft |
| D) | 5.5 ft |
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| 18 | A block of mass m slides down an inclined plane of height h and slope distances. The kinetic energy at the bottom will be equal to |
| A) | mgh |
| B) | ½mv² - Fs |
| C) | mgh - Fs |
| D) | mgh + Fs |
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| 19 | A 2-kg ball has a potential energy of 6400 J at a point A above the ground. What will its velocity be when it strikes the ground after being released from point A? |
| A) | 80 m/s |
| B) | 28.3 m/s |
| C) | 6400 m/s |
| D) | 800 m/s |
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| 20 | A bullet whose initial kinetic energy is 400 J strikes a block where an 8000-N resistive force brings it to a stop. The depth of penetration into the wood is approximately |
| A) | unknown for lack of information |
| B) | 0.2 m |
| C) | 0.5 m |
| D) | 0.05 m |
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| 21 | Three examples of potential energy are , , and . |
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| 22 | The work of a resultant external force on a body is equal to the change in of the body. |
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| 23 | The total mechanical energy of a body is the sum of its . This total is in the absence of friction. |
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| 24 | A force of 1 N acting through a distance of 1 m represents equal to 1 . |
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| 25 | is the rate at which work is done. |
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| 26 | The net work done by a number of forces acting on the same object is equal to the work of force. |
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| 27 | The kilowatthour is a unit of . |
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| 28 | When the resultant force on an object is opposite to the direction of displacement, the work is considered . |
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| 29 | Two things that are necessary in the performance of work are and . |
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| 30 | The product of force and velocity is a measure of . |