Question

A turn table is rotating in horizontal plane about its own axis at an angular velocity `90rpm` while a person is on the turn table at its edge. If he gently walks to the centre of table by which moment of inertia of system decreases by `25%`, then the time period of rotating of turn table is
A. `0.5 sec`
B. `1 sec`
C. `1.5 sec`
D. `2 sec`

Answer 1

Correct Answer - A
`I_(1)omega_(1)=I_(2)omega_(2), I_(1)=100,I_(2)=100-25=75`