| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.27 |
| Score | 0% | 65% |
A watt is the unit for which of the following?
power |
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mechanical advantage |
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work |
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energy |
Power is the rate at which work is done, P = w/t, or work per unit time. The watt (W) is the unit for power and is equal to 1 joule (or newton-meter) per second. Horsepower (hp) is another familiar unit of power used primarily for rating internal combustion engines. 1 hp equals 746 watts.
The work done by the sum of all forces acting on a particle equals the change in the kinetic energy of the particle. This defines which of the following?
work-energy theorem |
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mechanical advantage |
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conservation of mechanical energy |
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Pascal's law |
The work-energy theorem states that the work done by the sum of all forces acting on a particle equals the change in the kinetic energy of the particle. Simply put, work imparts kinetic energy to the matter upon which the work is being done.
| 1 | |
| -1 | |
| 0 | |
| 1 |
The mechanical advantage of a wheel and axle lies in the difference in radius between the inner (axle) wheel and the outer wheel. But, this mechanical advantage is only realized when the input effort and load are applied to different wheels. Applying both input effort and load to the same wheel results in a mechanical advantage of 1.
An object's resistance to changes in direction is known as:
kinetic energy |
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mass |
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weight |
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inertia |
The more mass a substance has the more force is required to move it or to change its direction. This resistance to changes in direction is known as inertia.
| 600 ft⋅lb | |
| None of these is correct | |
| 300 ft⋅lb | |
| 150 ft⋅lb |