Physics Rotational & Circular Motion NUMS 2023
PMDC Verified Question 45 of 95
The expression for centripetal force is:
A
\( F_c = m\omega^2 \)
B
\( F_c = mr\omega \)
C
\( F_c = mr\omega^2 \)
D
\( F_c = mr^2\omega \)
Tap any option to test your recall and reveal the step-by-step Propolis autopsy.

Propolis Cognitive Error Autopsy

Official Correct Choice:
Option C: \( F_c = mr\omega^2 \)
Concept:

Centripetal force is most fundamentally written as \( F_c = \frac{mv^2}{r} \). By substituting the rotational equivalent of velocity, we arrive at the angular format.

Formula:

$$ F_c = \frac{mv^2}{r} \quad \text{and} \quad v = r\omega $$

Solution:

  • Substitute \( (r\omega) \) into the velocity term: \( F_c = \frac{m(r\omega)^2}{r} \).
  • Square the terms: \( F_c = \frac{mr^2\omega^2}{r} \).
  • Cancel one 'r' from the numerator and denominator.
  • This yields the final angular expression: \( F_c = mr\omega^2 \).


Why other options are incorrect:

  • Option A is missing the radius dimension.
  • Option B is missing the square on the angular velocity.
  • Option D incorrectly squares the radius instead of the velocity.

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 Rotational & Circular Motion 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