An electric motor is used to lift the weight of 2.0N through a vertical distance of 100 cm in 4 sec. What is the power output of the motor?
Correct answer: B. 0.5 W
- A. 25 W
- B. 0.5 W
- C. 0.75 W
- D. 1 W
Explanation
W=2.0N×1.0m=2.0JNext, the time taken to lift the weight is 4 seconds. Now we can find the power:P =work/time=2/4=0.5Watt
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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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