JEE Main 2019 — Rotational Motion Question with Solution
From: JEE Main 2019 (Online) 12th April Morning Slot
Question
A person of mass M is, sitting on a swing of length L and swinging with an angular amplitude 0. If the
person stands up when the swing passes through its lowest point, the work done by him, assuming that his
center of mass moves by a distance ( << L), is close to;
Choose an option
Show full solutionCorrect option: A
Correct answer
Amg(1 + 02)
Step-by-step explanation
Angular momentum conservation
MV0L = MV1(L – )
Now
By, Binomial approximation
Here, V0 = maximum velocity =
So,
=
MV0L = MV1(L – )
Now
By, Binomial approximation
Here, V0 = maximum velocity =
So,
=
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