Question

Define 1 kWh.

Answer 1

1. One kilowatt-hour (kWh) is equal to the work done or energy consumed when a device of power $1kW$ is used for 1 hour.
2. The kilowatt-hour is not a standard unit in any formal system, but it is commonly used in electrical applications.

$$\begin{gathered} 1kilowatt-hour=1kilowatt\times 1hour \\ 1kilowatt-hour=1000watt\times 3600second \\ 1kilowatt-hour=3.6\times {10}^{6}wattsecond \\ i.e,1kWh=3.6\times {10}^{6}J \end{gathered}$$