A certain resistor dissipates 0.5 W when connected to a 3 V potential difference.When connected to a 1 V potential difference, this resistor will dissipate:
A)0.056 W
B)0.167 W
C)0.50 W
D)1.5 W
E)none of these

Question

Quizplus · Accepted Answer

Assuming the resistor has a constant resistance, we can use the formula for power dissipation:

P = V^2/R

where P is power, V is potential difference, and R is resistance.

When connected to a 3 V potential difference, the resistor dissipates 0.5 W, therefore:

0.5 W = 3^2/R
R = 18 ohms

When connected to a 1 V potential difference, the power dissipated is:

P = 1^2/18
P = 0.056 W

Therefore, the answer is choice A.

A Certain Resistor Dissipates 0