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An ice skater has her arms outstretched ...

An ice skater has her arms outstretched and is spinning with a rate of 2 rotations per second. Her moment of inertia at this instant is `1.48kgm^(2)`. She then pulls her arms inside to increase her rate of spin and her moment of inertia becomes `0.56kgm^(2)`. Calculate her new rate of rotation.

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To solve the problem, we will use the principle of conservation of angular momentum. The angular momentum of a system remains constant if no external torque acts on it. ### Step-by-Step Solution: 1. **Identify Initial Conditions**: - Initial moment of inertia, \( I_{\text{initial}} = 1.48 \, \text{kg m}^2 \) - Initial rate of rotation, \( f_{\text{initial}} = 2 \, \text{rotations per second} \) ...
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MODERN PUBLICATION-SYSTEMS OF PARTICLES AND ROTATIONAL MOTION-Chapter Practice Test (for Board Examination)
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  2. Can centre of mass of a body lie where there is absolutely no mass ?

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  3. Which component of linear momentum does not contribute to angular mome...

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  4. Can a body moving in a circular path be at equilibrium?

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  5. Does the moment of inertia of a body change with the speed of rotatio...

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  6. Two lenses, one convex and other concave, are of same mass and same ra...

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  7. Why the handles of the doors are at maximum distance from the hinges?

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  8. State and explain parallel axis theorem and perpendicular axis theorem...

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  9. If earth were to shrink suddenly, what would happen to the length of t...

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  10. The angular momenta of two bodies X and Y are equal and moment of iner...

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  11. (i) A person sits near the edge of a circular platform revolving with ...

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  12. Show that the angular momentum of a particle is equal to twice the pro...

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  13. Establish a relation between angular momentum and moment of inertia of...

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  16. The speed of the motor of an engine is 300 rpm. In 2 s, the speed incr...

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