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Why spin angular velocity of a star is g...

Why spin angular velocity of a star is greatly enhanced when it collapses under gravitational pull and becomes a neutron star ?

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On collapsing under gravitational pull, size of star decreases. Therefore, its moment of inertia decreases. As angular momentum `(L = I omega)` is conserved, and `I` decreases, therefore, spin angular velocity `omega` increases.
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PRADEEP-SYSTEMS OF PARTICLES AND ROTATIONAL MOTION-VERY SHORT ANSWER QUESTIONS
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  2. Is radius of gyration of a body constant quantity ?

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  3. There are two spheres of same mass and same radius, one is solid and o...

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  5. Name the rotational analogue of force. What are its units ?

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  7. Can a body in translatory motion have angular momentum ? Explain.

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  8. Why spin angular velocity of a star is greatly enhanced when it collap...

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  9. Fill in the blanks : (i) overset rarr(tau) = overset rarr(r ) xx … (...

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  10. How are torque and angular momentum related ?

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  11. Complete the statement : Angular momentum of a particle is equal to tw...

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  13. Write an expression for kinetic energy of rolling body.

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  15. Angle traced by a rotating body in nth seconds is theta(nth)=…………where...

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  17. Why does a solid sphere have smaller moment of inertia than a hollow c...

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  18. The variation of angular position theta, of a point on a rotating rigi...

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