Question

Name the largest and smallest practical units of energy.

Answer 1

Definition of energy:

Energy can be defined as the ability to do work. The SI unit of energy is joules (J).

Largest unit of energy:

1. The largest unit of energy is kilowatt-hour (kWh)
2. The relation between KWh and joules can be expressed as follows:

$$\begin{gathered} 1kWh=1kW\times 1h \\ =1000W\times 3600s \\ =3.6\times {10}^{6}J \end{gathered}$$

Smallest unit of energy:

1. The smallest unit of energy is electron volt (eV)
2. The relation between eV and joules can be expressed as follows:

$1eV=1.6\times {10}^{-19}J$

Therefore, the largest unit of energy is kilowatt-hour (kWh) and the smallest unit of energy is electron volt (eV).