Topic: Network Theory
A dc voltage V is applied at time $t=0$ to a series RC circuit. The steady state current is
- A. $V/R$
- B. $V/C$
- C. $\frac{V}{\sqrt{R^{2}+C^{2}}}$
- D. Zero
Answer: D. Zero
Explanation: For an RC circuit, the current response to a DC step is $i(t)=\frac{V}{R}e^{-t/RC}$. In the steady state ($t \to \infty$), the capacitor is fully charged and acts as an open circuit, making the current zero.