Question

State a relation between electrical power, resistance and potential difference in a circuit.

Answer 1

1. The rate at which electric energy is consumed, is known as electric power.
2. The $S.I$ unit of electric power $\left(P\right)$ is Watt or joule per second.
3. Potential difference is defined as the difference between the potentials at two point.
4. The S.I. unit of potential difference is joule per coulomb or volt $\left(V\right)$.
5. Resistance a measure of its opposition to the flow of electric current.
6. The SI unit of electric resistance is the $ohm\left(\Omega \right).$
7. The relation between electrical power, resistance and potential difference in a circuit is given by $P=\frac{V^2}{R}$
   Where $P-$power, $V-$voltage, $R-$resistance.

Therefore, expression for calculating electrical power in terms of current and resistance is $P=\frac{V^2}{R}$.