Collision between A and B
m×9=mv1+2mv2 (from momentum conservation)
e=1=9v2−v1
⇒v2=6msec−1,v1=−3msec−1
Collision between B and C
2m×6=4mv (from momentum conservation)
v=3ms−1
Three objects A,B and C are kept in a straight line on a frictionless horizontal surface. The masses of A,B and C are m,2m and 2m respectively. A…
JEE Main 2021 — Physics Mechanics
2021mcqmedium
Three objects A,B and C are kept in a straight line on a frictionless horizontal surface. The masses of A,B and C are m,2m and 2m respectively. A moves towards B with a speed of 9ms−1 and makes an elastic collision with it. Thereafter B makes a completely inelastic collision with C. All motions occur along the same straight line. The final speed of C is :
Official previous-year question
Held on 27 Jul 2021 · Verified 6 Jul 2026.
Options
- A
6ms−1
- B
9ms−1
- C
4ms−1
- D
3ms−1
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