Question

A current I flows through a resistor. A source maintains a potential difference of V across the resistor. The energy supplied by the source in time t is

(a) VI t²

(b) VI

(c) VI t

(d) VI / t

Answer 1

Correct option is (c) VI t

Electric power is the rate at which electric energy (E) is transferred in an electric circuit per unit time (t).

According to Ohm’s law, power is given as the product of voltage (V) and current (I) of a circuit.

P = VI

∴ P = E/t

VI = E/t

E = VI t

Therefore, the energy supplied in a circuit is given by E = VI t