A pump motor is used to deliver water at a certain rate from a given pipe. To obtain thrice as much as water from the same pipe in the same time, power of the motor has been increased:
Correct answer: A. 3 times
- A. 3 times
- B. 9 times
- C. 27 times
- D. 81 times
Explanation
Option A is correct.We know thatPower is given byP,=mgh/tPis directly proportional to m (For same height and time)P,=3mgh/t=3P (m,=3m)
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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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