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An inductor in a DC circuit, in STEADY STATE, acts as
Aan open circuit
Ba resistor of $R = L$
Ca voltage source
Da short circuit
Answer & Solution
Correct answer: D. a short circuit
1. INDUCTOR voltage: $v_L = L\,di/dt$.
2. In DC STEADY STATE: $di/dt = 0$ (current is constant), so $v_L = 0$.
3. ZERO voltage across an element means ZERO impedance → SHORT CIRCUIT.
4. The inductor still CARRIES current, but doesn't oppose it once steady state is reached.
5. Option A is the capacitor's DC steady state. Options B, C are wrong.
_Source: Tony Kuphaldt, "Lessons in Electric Circuits — DC", Vol I, Ch 15 (Inductors in DC)._
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