A simple ac circuit is composed of a capacitor connected across the terminals of an ac power source.If the frequency of the source is doubled,what happens to the reactance of the capacitor?
A)It increases by a factor of 4.
B)It increases by a factor of 2.
C)It increases by a factor of
D)It decreases by a factor of 2.
E)It decreases by a factor of 4.

Question

A simple ac circuit is composed of a capacitor connected across the terminals of an ac power source.If the frequency of the source is doubled,what happens to the reactance of the capacitor?
A)It increases by a factor of 4. 
B)It increases by a factor of 2. 
C)It increases by a factor of 
D)It decreases by a factor of 2. 
E)It decreases by a factor of 4.

Quizplus · Accepted Answer

The reactance of a capacitor is given by Xc = 1/(2πfC), where f is the frequency and C is the capacitance. Doubling the frequency will result in halving the reactance, so the correct answer is D) It decreases by a factor of 2.

A Simple Ac Circuit Is Composed of a Capacitor Connected