JEE Main 2025 — Physics Mechanics
2025mcqeasy
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/s. If we wait sufficiently long for elastic collision to happen, then vA=4 m/s,vB=2 m/s, vC=5 m/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 :
Official previous-year question
Held on 29 Jan 2025 · Verified 6 Jul 2026.
Options
- A
(A) is false but (R) is true
- B
Both (A) and (R) are true but (R) is NOT the correct explanation of (A)
- C
Both (A) and (R) are true and (R) is the correct explanation of (A)
- D
(A) is true but (R) is false
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