JEE Main 2021PhysicsCenter of Mass Momentum and CollisionEasyMCQ

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

JEE Main 2021 (26 Feb Shift 1)

Question

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R.

Assertion A : Body P having mass M moving with speed u has head-on collision elastically with another body Q having mass m initially at rest. If m≪M, body Q will have a maximum speed equal to 2u after collision.

Reason R : During elastic collision, the momentum and kinetic energy are both conserved.

In the light of the above statements, choose the most appropriate answer from the options given below:

Choose an option

Show full solutionCorrect option: C
Correct answer
CBoth A and R are correct and R is the correct explanation of A

Step-by-step explanation

For e=1 & second body at rest

V2=2m1u1 m1+m2=2uMM+m≃2u

Since M>>m

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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.