When a potential difference is applied between the two terminals of a conductor, an electric current is set up. Due to this, work is done and the electrons acquire energy. This electrical energy may be transformed into different forms of energy (e.g.- heat, light, mechanical energy etc.) according to the nature of the circuit.

Say, AB is a conductor of resistance R and Q amount of charge is flowing through it. The potential difference between the points A and B is V. We know, if the potential difference between the two terminals of a conductor is 1 volt and 1 coulomb charge flows through it, then the amount of work done or energy spent is joule. Now, if Q coulomb charge flows through the conductor, the amount of work done = VQ joule. Therefore, energy spent or the amount of energy converted is **W = VQ**

Again, Electric Current, **I = Q/t**

Or, **Q = It**

So, **W = VIt**

Using ohm’s law this relationship can be expressed as below,

**W = VIt = I ^{2}Rt = (V^{2}/R)t Joule**