Concept:The opposition of an inductor to alternating current is called inductive reactance (\(X_L = 2\pi f L\)). For steady direct current (\(f = 0\)), the reactance is zero, allowing DC to pass with minimal drop while presenting high impedance to high-frequency AC ripple.
Formula:$$X_L = 2\pi f L$$
$$\text{For DC } (f = 0): X_L = 0; \quad \text{For AC Ripple } (f > 0): X_L = 2\pi f L > 0$$
Solution:- Direct current has frequency \(f = 0\text{ Hz}\), so \(X_L = 0\,\Omega\) (ideal inductor acts as a short circuit for DC).
- AC ripple has frequency \(f = 50\text{ Hz}\) or \(100\text{ Hz}\), so \(X_L = 2\pi f L \gg 0\,\Omega\) (opposes AC fluctuation).
- Therefore, a series inductor blocks AC ripple while permitting DC to flow freely to the load.
Why other options are incorrect:- Option B: Inverts the fundamental frequency response of an inductor.
- Option C: Electrostatic storage describes a capacitor; an inductor stores energy in a magnetic field.
- Option D: Inductors dissipate negligible energy in ideal cases and produce no nuclear radiation.
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