Question

A coil receives an electric power of 4500 W from a supplied voltage of 240 V. What is the resistance of the coil?

Answer 1

The power of electrical current

$$P=\frac{V^2}{R}$$

Hence, the resistance of the coil

$$R=\frac{V^2}{P}=\frac{240^2}{4500}=12.8\:\Omega$$