Passage - III : A long horizontal plank of mass 'm' is lying on a smooth horizontal surface. A sphere of same mass 'm' and radius 'r' is spinned about its own axis with angular velocity omega_(0) and gently placed on the plank at t=0. The coefficient of friction between the plank and the sphere is mu. After some time the pure rolling of the sphere on the plank will start. Find the time t at which the pure rolling starts.

Passage - III : A long horizontal plank of mass 'm' is lying on a smo

1.	Passage - III : A long horizontal plank of mass 'm' is lying on a smooth horizontal surface. A sphere of same mass 'm' and radius 'r' is spinned about its own axis with angular velocity omega_(0) and gently placed on the plank at t=0. The coefficient of friction between the plank and the sphere is mu. After some time the pure rolling of the sphere on the plank will start. Find the time t at which the pure rolling starts.
Answer» `(omega_(0)R)/(9mug)` `(2omega_(0)r)/(9mug)` `(omega_(0)r)/(3mug)` `(2omega_(0)r)/(mug)` Answer :B