Center of Mass, Momentum & Collision

JEE Main level, single correct, medium

83 of 130

Question 83 of 130

Given below are two statements. One is labelled as Assertion (A) and the other is labelled as Reason (R).

Assertion (A) :


Three identical spheres of same mass undergo one dimensional motion as shown in figure with initial velocities
vA=5 m/s,vB=2 m/s,vC=4 m/sv_{\mathrm{A}}=5 \mathrm{~m} / \mathrm{s}, v_{\mathrm{B}}=2 \mathrm{~m} / \mathrm{s}, v_{\mathrm{C}}=4 \mathrm{~m} / \mathrm{s}. If we wait sufficiently long for elastic collision to happen, then vA=4 m/s,vB=2 m/sv_{\mathrm{A}}=4 \mathrm{~m} / \mathrm{s}, v_{\mathrm{B}}=2 \mathrm{~m} / \mathrm{s}, vC=5 m/sv_{\mathrm{C}}=5 \mathrm{~m} / \mathrm{s} will be the final velocities.

Reason (R): In an elastic collision between identical masses, two objects exchange their velocities.

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

Show answer and solution

Answer: (A) (A) is false but (R) is true

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