physics ncert solutions class 11th Physics Class 11th System of Particles and Rotational Motion

7.3 A child sits stationary at one end of a long trolley moving uniformly with a speed V on a smooth horizontal floor. If the child gets up and runs about on the trolley in any manner, what is the speed of the CM of the (trolley + child) system?

3 Views | Posted 4 months ago

1 Answer

Answered by

Vishal Baghel | Contributor-Level 10

4 months ago

The child is sitting on the trolley and there is no external force, hence it is a single system. The velocity of the centre of mass will not change, irrespective of any internal motion.

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