Question

1kWh is equal to

• A. 3.6×10⁶ MJ
• B. 3.6×10⁵ MJ
• C. 3.6×10² MJ
• D. 3.6 MJ

Answer 1

The correct option is D

3.6 MJ

1. 1 kilowatt-hour is defined as the energy consumed by a device of power 1 kilowatt in 1 hour.
2. 1 kilowatt is the energy equivalent to 1 unit of electricity.
3. 1 unit = 1kilowatt- hour(kWh)
4. The SI unit of energy is joule.
5. $$\begin{gathered} Energy\left(J\right)=Power\left(W\right)\times Time\left(s\right) \\ 1J=1Ws \end{gathered}$$
6. $$\begin{gathered} 1kWh=1000W\times 1hour \\ =1000W\times 60\times 60s \\ =3.6x{10}^{6}J \\ =3.6MJ \end{gathered}$$

Hence, Option (d) is correct.