JEE Main 2021 — Rotational Motion Question with Solution
From: JEE Main 2021 (Online) 16th March Morning Shift
Question
Consider a 20 kg uniform circular disk of radius 0.2 m. It is pin supported at its center and is at rest initially. The disk is acted upon by a constant force F = 20 N through a massless string wrapped around is periphery as shown in the figure.
Suppose the disk makes n number of revolutions to attain an angular speed of 50 rad s1.
The value of n, to the nearest integer, is __________.
[Given : In one complete revolution, the disk rotates by 6.28 rad]
Suppose the disk makes n number of revolutions to attain an angular speed of 50 rad s1.
The value of n, to the nearest integer, is __________.
[Given : In one complete revolution, the disk rotates by 6.28 rad]
This question includes a diagram. The text above accompanies the figure.
Enter your answer
Show full solutionCorrect answer: 125
Correct answer
125
Step-by-step explanation
rad/s2
rad
No. of revolution revolution
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This is a previous-year question from JEE Main 2021, covering the Rotational Motion chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.