Question

When the supply frequency increases, what happens to the capacitive reactance in the circuit?

(a) Increases

(b) Decreases

(c) Remains the same

(d) Becomes zero

The question was posed to me in an interview for job.

My question is based upon Capacitance in portion Capacitance and Capacitors of Basic Electrical Engineering

Answer 1

Right answer is (b) Decreases

The explanation: The expression for capacitive reactance is: Xc=1/(2*pi*f*C). This relation shows that frequency is inversely related to capacitive reactance. Hence, as supply frequency increases, the capacitive reactance decreases.