An electric heater with a p.d of 240 V connected across its terminals has a total resistance of 960Ω. find the power rating of the heater.

Answer Details

Power, P = (V^2)/R, where V is the voltage and R is the resistance. Given that the p.d of the electric heater is 240 V and the total resistance is 960Ω, we can calculate the power rating of the heater as follows:
P = (240^2)/960
P = 57600/960
P = 60 W
Therefore, the power rating of the electric heater is 60 W. Answer option (D) is correct.