Question

An electric heater is rated 1500 W. How much energy does it use in 10 hours?

Answer 1

Energy consumed by an electric heater can be obtained with the help of the expression,
$P=\frac{W}{T}$
where, power rating of the heater, $P=1500W=1.5kW$
time for which the heater has operated, $T=10h$
Work done = Energy consumed by the heater
$\therefore$Energy consumed =$Power\times Time$ $=1.5\times 10=15kWh$
Hence, the energy consumed by the heater in $10h$ is $15kWh$.