Question

When a current of 4.0 A passes through a certain resistor for 10 minutes, 2.88 × 10⁴ J of heat are produced. Calculate

(a) the power of the resistor.
(b) the voltage across the resistor.

Answer 1

I = 4.0 A
H = 2.88 x 10⁴ J
t = 10 minutes = 10 x 60 = 600 s

(a) Power = $\frac{H}{t}=\frac{2.88\mathrm{x}{10}^4}{600}=48\mathrm{W}$

(b) V = $\frac{P}{I}=\frac{48}{4}=12\mathrm{V}$