Question

Initially two stable particles x and y start moving towards each other under mutual attraction. If at one time tbe velocities are v and 2v respectively, what will velocity of centre of mass be

Answer 1

Answer:

Zero

Explanation:

Initially the particles are at rest i.e. the velocity of their centre of mass is zero

Since the particles do not have any external force acting therefore the momentum will be conserved

Therefore, the final momentum of the centre of mass will also be zero because the mass is non zero

Hence, the velocity of the centre of mass will be zero.

Hope this helps.

Answer 2

Answer:

As initially, both the particles were at rest, therefore, velocity of the centre of mass was zero and there is no external force on the system so the speed of the centre of mass remains constant i.e, it should be equal to zero.