Exams › JEE Advanced › Physics
A putty of mass m = 1 kg moving with speed v0 = 4 m/s strikes one end of a dumbbell placed on a smooth horizontal table and sticks to it. The dumbbell consists of two identical balls each of mass m = 1 kg connected by a massless rod of length 2 m (ball-to-ball). The putty moves in the plane of the dumbbell and hits one end ball. How much thermal energy (in J) is produced in the collision?
- 1
- 2
- 3
- 4
Correct answer: 3
Solution
The putty sticks to one end ball. After collision, the system (putty+dumbbell) moves with CM velocity and also rotates. Energy not stored as KE becomes thermal energy (heat due to inelastic collision).
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