Question

16.A sphere of radius r specific heat s is rotated about an axis passing through its centre at a speed of n rotations per second. It is suddenly stopped and 50% of its energy is used in increasing its temperature. Then the rise in temperature of the sphere is A. (2/5)π²n²r²/s B. (1/10)π²n²/r²s C. (7/8)πr²n²s D. 5[πrn/145]²

Answer 1