Power
Power is the rate at which work is done, which means how fast a work is done.
Formula:Power is the rate at which work is done, which means how fast a work is done.
Example:
An electric motor takes 20 s to lift a box of mass 20kg to a height of 1.5 m. Find the amount of work done by the machine and hence find the power of the electric motor.
Answer:
Work done,
W = mgh = (20)(10)(1.5) = 300J
Power,
\[ P = \frac{W}{t} = \frac{{300}}{{20}} = 15J\]
An electric motor takes 20 s to lift a box of mass 20kg to a height of 1.5 m. Find the amount of work done by the machine and hence find the power of the electric motor.
Answer:
Work done,
W = mgh = (20)(10)(1.5) = 300J
Power,
\[ P = \frac{W}{t} = \frac{{300}}{{20}} = 15J\]