Q.

A solid sphere with uniform density and radius R is rotating initially with constant angular velocity (ω1) about its diameter. After sometime during the rotation its starts loosing mass at a uniform rate, with no change in its shape. The angular velocity of the sphere when its radius become R/2 is xω1. The value of x is _________.           [2025]


Ans.

(32)

When the sphere is of radius R, its mass is M, when radius is reduced to R2, mass will reduced to M8

Angular momentum will remain conserve.

L1=L2  I1ω1=I2ω2

(25MR2)ω1=(25(M8)(R2)2)ω2

ω2=32ω1 value of x is 32.