A solid sphere is rotating in free space. If the radius of sphere is increased keeping mass same which one of the following will not be affected? |
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a) |
Angular velocity |
b) |
Angular momentum |
c) |
Moment of inertia |
d) |
Rotational Kinetic energy |

A solid sphere is rotating in free space. If the radius of sphere is increased keeping mass same which one of the following will not be affected? |
|||||||

a) |
Angular velocity |
b) |
Angular momentum |
c) |
Moment of inertia |
d) |
Rotational Kinetic energy |

1 Answer

127 votes

**(b)**

A solid sphere is rotating in free space, so there is no external torque.

,

But the rate of change of angular momentum is equal to the torque.

then

or

or constant

But , if we increase the radius of the sphere then its moment of inertia increases. From , its angular velocity decreases.

Also we know that the rotational energy

Hence, decreases as is increases.

127 votes

127