JEE Main 2020PhysicsCenter of Mass Momentum and CollisionHardNumerical

JEE Main 2020 — Center of Mass Momentum and Collision Question with Solution

JEE Main 2020 (02 Sep Shift 2)

Question

A particle of mass m is moving along the x-axis with initial velocity ui^. It collides elastically with a particle of mass 10m at rest and then moves with half its initial kinetic energy (see figure). If  sin θ1=nsin θ2 then value of n is ________.

  

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Show full solutionCorrect answer: 10
Correct answer
10

Step-by-step explanation

From momentum conservation in perpendicular direction of initial motion.
mv1sinθ1=10mv2sinθ2
Given that 12mu212=12mv12  …….(2)
From equation (1) & (2)
sinθ1=10sinθ2
n=10

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About this question

This is a previous-year question from JEE Main 2020, 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.