If the voltage across a circuit of constant resistance is doubled,the power dissipated by that circuit will
A)be four times as large.
B)be two times as large.
C)decrease to one-half the original power.
D)decrease to one-fourth the original power.

Question

Quizplus · Accepted Answer

According to Ohm's law, power dissipation is given by P = V^2/R, where V is the voltage across the circuit and R is the resistance of the circuit.

If the voltage across the circuit is doubled, the new voltage is 2V. Substituting this in the formula, we get:

P = (2V)^2/R = 4V^2/R

Therefore, the power dissipated by the circuit is four times as large.

If the Voltage Across a Circuit of Constant Resistance Is