Question

Why does capacitor block dc signal at steady state?

(a) due to high frequency of dc signal

(b) due to zero frequency of dc signal

(c) capacitor doesnot pass any current at steady state

(d) due to zero frequency of dc signal

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Question is taken from Capacitance and the Capacitor topic in division Capacitance and Capacitors of Basic Electrical Engineering

Answer 1

The correct answer is (d) due to zero frequency of dc signal

The explanation is: Frequency of dc signal is zero. So, Capacitive reactance XC=1/2πfc becomes infinite and capacitor behaves as open circuit for dc signal. Hence, capacitor block dc signal.