JEE Main 2020 — Rotational Motion Question with Solution
From: JEE Main 2020 (Online) 5th September Morning Slot
Question
A wheel is rotating freely with an angular speed
on a shaft. The moment of inertia of the
wheel is I and the moment of inertia of the
shaft is negligible. Another wheel of moment of
inertia 3I initially at rest is suddenly coupled to
the same shaft. The resultant fractional loss in
the kinetic energy of the system is :
Choose an option
Show full solutionCorrect option: D
Correct answer
D
Step-by-step explanation
Applying Angular Momentum conservation
Fractional loss
=
Fractional loss
=
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This is a previous-year question from JEE Main 2020, 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.