Physics Alternating Current PMDC Conceptual Practice
PMDC Verified Question 45 of 127
What is the form factor of a pure sinusoidal alternating voltage waveform?
A
\(1.11\)
B
\(1.41\)
C
\(0.707\)
D
\(0.637\)
Tap any option to test your recall and reveal the step-by-step Propolis autopsy.

Propolis Cognitive Error Autopsy

Official Correct Choice:
Option A: \(1.11\)
Concept:

The form factor of an alternating waveform is defined as the ratio of its root-mean-square (RMS) value to its average value over a half-cycle.

Formula / Reaction:

$$\text{Form Factor} = \frac{V_{\text{rms}}}{V_{\text{avg(half)}}} = \frac{V_0 / \sqrt{2}}{2V_0 / \pi} = \frac{\pi}{2\sqrt{2}} \approx 1.11$$

Solution:

  • \(V_{\text{rms}} = \frac{V_0}{\sqrt{2}} \approx 0.707 V_0\).


  • \(V_{\text{avg(half)}} = \frac{2V_0}{\pi} \approx 0.637 V_0\).


  • \(\text{Form Factor} = \frac{0.707}{0.637} \approx 1.11\).


Why other options are incorrect:

  • Opt_B: \(1.414\) (\(\sqrt{2}\)) is the peak factor (crest factor), not the form factor.


  • Opt_C: \(0.707\) is the ratio \(V_{\text{rms}} / V_0\).


  • Opt_D: \(0.637\) is the ratio \(V_{\text{avg(half)}} / V_0\).

Quality & Fidelity Assurance: Every question on BeambePrep is rigorously curated against the official PMDC syllabus with zero filler, zero out-of-syllabus content, and zero typos. When an authentic past paper originally contained a historical mistake or ambiguity from the examining board (such as UHS or NUMS), BeambePrep faithfully reflects the original paper while detailing the nuance and scientific consensus in the autopsy above.

Previous Question All Alternating Current MCQs Next Question

Want to solve full-length papers under timed exam conditions?

Practice with zero-scroll lockdown sprints, dynamic latency zone timers, live peer selection telemetry, and the automated Amber mistake recovery loop.

Enter Arena Sprint iOS App Android App