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A man standing on a platform holds weigh...

A man standing on a platform holds weights in his outstretched arms. The system is rotated about a central vertical axis. If the man now pulls the weights inwards close to his body then

A

the angular velocity of the system will increase

B

the angular momentum of the system will remain constant

C

the kinetic energy of the system will increase

D

all of the above

Text Solution

Verified by Experts

I will decrease
`thereforeomega` will increase (as `L=Iomega=` constant)
`KE=(L^(2))/(2I)` will increase as `I` is decreasing.
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DC PANDEY-ROTATIONAL MECHANICS-Level 1 Objective
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  2. A shaft initially rotating at 1725 rpm is brought to rest uniformly in...

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  3. A man standing on a platform holds weights in his outstretched arms. T...

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  4. Moment of inertia of a thin semicircular disc (mass - M & radius = R) ...

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  5. Two bodies A and B made of same material have the moment of inertial i...

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  6. When a sphere rolls down an inclined plane, then identity the correct ...

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  7. A circular table rotates about a vertical axis with a constant angular...

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  8. If R is the radius of gyration of a body of mass M and radius r, then ...

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  9. A solid sphere rolls down two different inclined planes of the same he...

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  10. For the same total mass, which of the following will have the largest ...

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  11. A disc and a solid sphere of same mass and radius roll down an incline...

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  12. A horizontal disc rotates freely with angular velocity omega about a v...

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  13. A solid homogeneous sphere is moving on a rough horizontal surface, pa...

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  14. A particle of mass m=3kg moves along a straight line 4y-3x=2 where x a...

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  15. A solid sphere rolls without slipping on a rough horizontal floor, mov...

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  16. Ler l be the moment of inertia of a uniform square plate about an axi...

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  17. A spool is pulled horizontally on rough surface by two equal and oppos...

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  18. Two identical discs are positioned on a vertical axis as shown in the ...

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