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A child is standing with folded hands at...

A child is standing with folded hands at the center of a platform rotating about its central axis. The kinetic energy of the system is `K`. The child now stretches his arms so that the moment of inertia of the system doubles. The kinetic energy of the system now is

A

2K

B

`(K)/(2)`

C

`(K)/(4)`

D

4K

Text Solution

Verified by Experts

The correct Answer is:
B
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DISHA PUBLICATION-SYSTEM OF PARTICLES & ROTATIONAL MOTION -EXERCISE-2 : CONCEPT APPLICATOR
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