Question

The miniature lamp carries a current of 0.28 A when connected to a 4.5 V voltage source. Calculate the lamp power.

Answer 1

By definition, the power is:

$$P = UI$$

where $U$ is a voltage and $I$ is a current. Thus, obtain:

$$P = 4.5V\times 0.28A = 1.26W$$

Answer. 1.26 W.