Express your answer in

(i) kWh

(ii) joule.

Solutions:

Expression for the Energy consumed is as follows –

Energy = power × time

(i) Substituting values from the questions and we have –

Energy = 3 kW × 10 h = 30 kWh

(ii) We know that , 1 kilowatt hour (kWh) = 3.6 × 10⁶ J

So, Energy in Joules becomes –

30 kWh = 30 × 3.6 × 10⁶ J

Energy (Joules) = 1.08 × 10⁸ J