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Question 30568
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Center of Mass, Momentum and Collision: JEE — Restitution Energy MCQ

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JEE — Restitution EnergyHardQuestion 30568

Question

Two equal masses (m) with e = 0 collide (u₁ = v, u₂ = 0). Energy lost is:
  1. A
    mv²/4
    Correct
  2. B
    mv²/2
  3. C
    mv²
  4. D
    0

Correct answer

mv²/4

Explanation

e = 0: perfectly inelastic → v_f = v/2. KE_lost = ½mv² − ½(2m)(v/2)² = mv²/2 − mv²/4 = mv²/4.

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