Concept:The ripple factor (\( r \)) quantifies the effectiveness of a rectifier by measuring the unwanted AC ripple voltage relative to the desired DC output voltage.
Formula:$$r = \frac{V_{\text{ac,rms}}}{V_{\text{dc}}} = \frac{\sqrt{V_{\text{rms}}^2 - V_{\text{dc}}^2}}{V_{\text{dc}}} = \sqrt{\left(\frac{V_{\text{rms}}}{V_{\text{dc}}}\right)^2 - 1} = \sqrt{\text{FF}^2 - 1}$$
Solution:- \( V_{\text{ac,rms}} \) is the RMS value of the AC ripple remaining in the output.
- \( V_{\text{dc}} \) is the average DC output voltage.
- The ratio \( V_{\text{ac,rms}} / V_{\text{dc}} \) gives the ripple factor \( r \).
Why other options are incorrect:- Option A: Peak-to-average ratio defines the crest factor, not the ripple factor.
- Option C: The ratio of DC power to AC power defines the rectification efficiency \( \eta \).
- Option D: Resistance ratio relates to circuit losses, not waveform ripple content.
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