JEE Main 2021PhysicsLaws of MotionHardNumerical

JEE Main 2021Laws of Motion Question with Solution

JEE Main 2021 (20 Jul Shift 2)

Question

A body of mass m is launched up on a rough inclined plane making an angle of 30° with the horizontal. The coefficient of friction between the body and plane is x5 if the time of ascent is half of the time of descent. The value of x is

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Show full solutionCorrect answer: 3
Correct answer
3

Step-by-step explanation

ta=12td

2 saa=122 sad i

aa=gsinθ+μgcosθ

=g2+32μg

ad=gsinθ-μgcosθ

=g2-32μg

Using the above values of aa and ad and putting in
equation i, we will get, μ=35

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About this question

This is a previous-year question from JEE Main 2021, covering the Laws of 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.