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A particle of mass m with kinetic energy K and momentum p collides head-on elastically with a stationary particle of mass 2m. After the collision, match the quantities in Column I with their values in Column II. Column I: (A) Momentum of first particle (B) Momentum of second particle (C) Kinetic energy of first particle (D) Kinetic energy of second particle Column II: (P) (4/3)p (Q) K/9 (R) -p/3 (S) (8/9)K (T) None

1. (A)-R, (B)-P, (C)-Q, (D)-S
2. (A)-P, (B)-R, (C)-S, (D)-Q
3. (A)-S, (B)-Q, (C)-R, (D)-P
4. (A)-T, (B)-T, (C)-T, (D)-T

Correct answer: (A)-R, (B)-P, (C)-Q, (D)-S

Solution

With m1 = m, m2 = 2m: first particle rebounds with momentum -p/3 (R) and KE K/9 (Q); second particle has momentum (4/3)p (P) and KE (8/9)K (S).

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