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A boy comes running and sits on a rotati...

A boy comes running and sits on a rotating platform. What is conserved ?

A

kinetic energy

B

angular momentum

C

linear momentum

D

none of these.

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The correct Answer is:
B
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VMC MODULES ENGLISH-SYSTEM OF PARTICLES AND ROTATIONAL MOTION-IMPECCABLE
  1. A boy comes running and sits on a rotating platform. What is conserved...

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  2. The angular momentum of body remains conserve if :

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  3. A circular disc is to be made using iron and aluminium. To keep its mo...

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  4. If rotational kinetic energy is 50% of total kinetic energy then the ...

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  5. A person is standing on the edge of a circular platform, which is movi...

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  6. A thin circular ring of mass M and radius r is rotating about its axis...

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  7. A solid cylinder of mass M and radius R rolls without slipping down an...

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  8. A bull rolls without slipping. The radius of gyration of the ball abou...

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  9. The moment of inertia in rotational motion is equivalent to :

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  10. Two rods each of mass m and length 1 are joined at the centre to form ...

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  11. A wheel has moment of inertia 5 xx 10^(-3) kg m^(2) and is making 20 "...

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  12. The ratio of the radii of gyration of a circular disc about a tangenti...

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  13. A round disc of moment of inertia I2 about its axis perpendicular to i...

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  14. Three particles, each of mass m are situated at the vertices of an equ...

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  15. A wheel having moment of inertia 2 kg m^(2) about its vertical axis, r...

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  16. In an orbital motion, the angular momentum vector is :

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  17. A solid cylinder of mass 20kg has length 1 m and radius 0.2 m. Then it...

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  18. A constant torque acting on a uniform circular changes its angular mom...

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  19. A dancer is standing on a rotating platform taking two sphere on her ...

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  20. The rate of change of angular momentum is called

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