How is 'power' defined in physics?
AThe work done while transferring energy from one body to another
BThe rate of doing work or rate of energy transfer
CThe amount of work done in exactly one minute
DThe force that is applied to lift a heavy load
Answer & Solution
Correct answer: B. The rate of doing work or rate of energy transfer
1. Power is defined as the rate at which work is done.
2. Equivalently, it is the rate of energy transfer per unit time.
3. Its SI unit is the watt (1 W = 1 J/s).
_Source: RRB Group D CEN-02/2018 PYQ, Q.3._
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