Concept:Rectification efficiency \( \eta \) is the ratio of useful DC output power delivered to the load resistor \( R_L \) to the total AC input power consumed by the circuit (diode resistance \( r_f \) plus \( R_L \)).
Formula:$$\eta = \frac{P_{\text{dc}}}{P_{\text{ac}}} = \frac{I_{\text{dc}}^2 R_L}{I_{\text{rms}}^2 (r_f + R_L)}$$
Solution:- DC power delivered to the load: \( P_{\text{dc}} = I_{\text{dc}}^2 R_L \).
- Total AC power supplied to the circuit: \( P_{\text{ac}} = I_{\text{rms}}^2 (r_f + R_L) \).
- Dividing \( P_{\text{dc}} \) by \( P_{\text{ac}} \) gives the conversion efficiency \( \eta \).
Why other options are incorrect:- Option B: This inverts the ratio of AC power to DC power.
- Option C: \( r_f / R_L \) is the resistance ratio, which relates to circuit losses rather than total efficiency.
- Option D: \( I_{\text{dc}} / I_{\text{rms}} \) is the reciprocal of the Form Factor, not the power efficiency.
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