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A child is standing at one end of a long...

A child is standing at one end of a long trolley moving with a speed v on a smooth horizontal track. If the child starts running towards the other end of the trolley with a speed u, the centre of mass of the system (trolley + child) will move with a speed :

A

v

B

`(v-u)`

C

`(v+u)`

D

zero

Text Solution

Verified by Experts

The correct Answer is:
A
Since there is no external force
`therefore` speed of centre of mass will not change
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