Question

How many joules of energy are equal to one kilowatt hour?

Answer 1

Definition of electric energy:

The product of power and time i.e. electric energy consumed by an electric appliance or the amount of work done is termed as electric energy.

Conversion of joules to kilowatt hour:

1. $1$ kilowatt hour $=1000$ watt hour
2. $1$ hour $=60$ minutes =$60\times 60s$

Therefore,

$$\begin{gathered} 1KwH=1000\frac{J}{s}\times (60\times 60)s \\ 1KwH=3600000J \\ 1KwH=3.6\times {10}^{6}J \end{gathered}$$

Therefore, one kilowatt hour is equal to $3.6\times {10}^6$ Joules of energy.