An 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) 0.5 W
B) 0.167 W
C) 1.5 W
D) 0.056 W
E) none of these

Question

Quizplus · Accepted Answer

The power dissipated by a resistor is given by the formula:

P = V^2/R

We are given that when the resistor is connected to a 3 V potential difference, it dissipates 0.5 W. Using the above formula and rearranging for R, we can find the resistance of the resistor:

0.5 W = (3 V)^2/R

R = 18 Ω

Now we can use the same formula to find the power dissipated when the resistor is connected to a 1 V potential difference:

P = (1 V)^2/18 Ω

P = 0.056 W

Therefore, the answer is choice D, 0.056 W.

An Certain Resistor Dissipates 0