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Two particles which are initially at rest, move towards each other under the action of their internal attraction. If their speeds are and at any instant, then the speed of centre of mass of the system will be:

  1. A
  2. B
  3. C
  4. D

Solution & Step-by-step Explanation

In the absence of any external force, the velocity of the center of mass of a system remains constant.

Since the particles were initially at rest, .
Thus, the speed of the center of mass remains zero at any instant.

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Two particles which are initially at rest, move towards each other under the action of their internal attraction. If their speeds are and at any instant, then the speed of centre of mass of the system will be:
A
B
C
D

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MechanicsCenter of MassInternal Force

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