A metal sphere of radius rand specific heat S is rotated about an axis passing through its centre at a speed of n rotations per second. It is stopped and 50% of its energy is used in increasing its temperature, then the raise in temperature of the sphere is

A metal sphere of radius rand specific heat S is rotated about an axis

1.	A metal sphere of radius rand specific heat S is rotated about an axis passing through its centre at a speed of n rotations per second. It is stopped and 50% of its energy is used in increasing its temperature, then the raise in temperature of the sphere is
Answer» ` (2)/(5) (pi^(2) n^(2) R^(2) )/( S)` `( 1)/( 10) ( pi^(2) n^(2) )/( r^(2) S)` `( 7)/( 8) pi r^(2) n^(2) S` `( 5 (pi r n))/( 14S)` Answer :A