Question

A motor expends a given amount of energy in a certain period of time. If twice the energy is expended in half the time, its power is:

Answer 1

Energy per unit of time is known as power

so here let say initial power is P in which energy E expended in time interval t

so we can say

$P = \frac{E}{t}$

now energy expended is double while it took half time

so new power expended will be

$P' = \frac{2E}{t/2}$

$P' = \frac{4E}{t}$

so here we can say that now the power expended will be 4 times the initial power