Raising the current through a resistor from 8.50 A to 11.3 A increases the power by
A) 33%.
B) 77%.
C) 113%.
D) 157%.
E) 0% (no change).

Question

Quizplus · Accepted Answer

The power dissipated in a resistor is given by $P = I^2R$, where $P$ is the power, $I$ is the current, and $R$ is the resistance. When the current is increased, the power increases by the square of the ratio of the currents. So, the increase in power is given by $\left(\frac{11.3}{8.5}\right)^2 = 1.77$ times the original power, or a 77% increase.

Raising the Current Through a Resistor from 8