Question

A solid sphere is rotating about one of its diameter
with angular velocity o. If it is heated up so that its
radius increase to double of its original value, then
its angular velocity becomes​

Answer 1

n2ω Explanation: for solid sphere, MI = (2/5)MR2 angular momentum is always conserved. L1 = L2 I1ω1 = I2ω2 here ω1 = ω hence ω2 = [(I1ω) / I2] (1) Initial MI = I1 = (2/5)MR12 Radius is reduced to (1/n) of original value hence R2 = (R1 / n) (2) hence new MI = I2 = (2/5)MR22 from (1) ω2 = (ω)[{(2/5)MR12} / {(2/5)MR22}] = (ω)(R1 / R2)2 ω2 = ω ∙ n2 from (2) Read more on Sarthaks.com - https://www.sarthaks.com/324965/solid-sphere-rotating-about-diameter-angular-velocity-cools-radius-reduces-original-value