A heavy circular disc is revolving in a horizontal plane about the centre which is fixed. An insect of mass `1/n th` that of the disc walks from the centre along a radius and then flies away. Show that the final angular velocity is `n/(n+2)` times the original angular velocity of the disc.

Explanation

`I_(1)omega_(2) =I_(2)omega_(2) , (1//2) mr^(2) + (1//n) mr^(2)]omega_(2), omega_(2) = nomega_(1)//n +2`