Rotation

Don't know the answer.

@KuldeepJaidev work done will be change in kinetic energy.
W= initial kinetic energy 0
KE= 1/2 mv^2 + 1/2 I w^2
= 1/2 mv^2 + 1/2 (2/5 mr^2) (v/r)^2
=1/2 mv^2 + 1/5 mv^2
=7/10 mv^2

@RIDDHISHAH This is Hollow sphere I should be equal to 2/3MR².

@KuldeepJaidev yeah fine substitute 2/3... answer will be 5/6 mv^2