The average power and instantaneous power become equal if work is done at __________________?
Correct answer: C. at uniform rate
- A. any rate
- B. at variable rate
- C. at uniform rate
- D. at high rate
Explanation
Average power is total work divided by total time, while instantaneous power is the rate of doing work at a particular instant. They are equal when work is done at a uniform rate, because the rate has the same value throughout. The likely wrong choice is b because variable-rate work generally makes instantaneous power change with time.
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About Power
Power is the rate at which work is done or energy is transferred, with average power calculated over a time interval and instantaneous power found from P = Fv when force and velocity are aligned. Work includes units, mechanical efficiency, and the distinction between power and total work or energy.
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