JEE Main 2021PhysicsCenter of Mass Momentum and CollisionMediumMCQ

JEE Main 2021 — Center of Mass Momentum and Collision Question with Solution

JEE Main 2021 (18 Mar Shift 2)

Question

An object of mass m1 collides with another object of mass m2, which is at rest. After the collision the objects move with equal speeds in opposite direction. The ratio of the masses m2:m1 is :

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Show full solutionCorrect option: A
Correct answer
A3:1

Step-by-step explanation

m1v1=-m1v+m2v

v1=-v+m2 m1v

v1+vv=m2 m1

e=2vv1=1

v=v12

v1+v1/2v1/2=m2 m1

3=m2 m1

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About this question

This is a previous-year question from JEE Main 2021, covering the Center of Mass Momentum and Collision 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.