A horizontal force `F` is applied at the centre of solid sphere placed over a plank. The minimum coefficient of friction between plank and sphere required for pure rolling is `mu_(1)` when plank is kept at rest ad `mu_(2)` when plank can move, then `mu_(2)ltmu_(1)`
Reason: Work done by frictional force on the sphere in both cases is zero.

Chain of mass M length L kept on rough sphere. mu is coefficient if friction between sphere and chain F is minimum force required to slide chain

A solid sphere of mass m and radius R is placed over a plank of same mass m . There is sufficient friction between sphere and plank to prevent slipping. Force of friction between sphere and plank is

A solid sphere of mass m and radius R is placed over a plank of same mass m . There is sufficient friction between sphere and plank to prevent slipping. Force of friction between sphere and plank is

A solid sphere of mass m and radius R is placed over a plank of same mass m . There is sufficient friction between sphere and plank to prevent slipping. Angular acceleration of sphere is

A solid sphere of mass m and radius R is placed over a plank of same mass m . There is sufficient friction between sphere and plank to prevent slipping. Angular acceleration of sphere is

In the figure shown, a solid sphere of mass 'm' and radius r is released from a height 6r to slide down a smooth surface. A plank of same mass 'm' touches the horizontal portion of the surface at the ground. The co-efficient of friction between the plank and the sphere is mu and that between the plank and the ground is mu//4 . Find the work done by the friction force between the plank and the ground till the sphere starts pure rolling on the plank. Neglect the height of the plank.

In the figure shown, a solid sphere of mass 'm' and radius r is released from a height 6r to slide down a smooth surface. A plank of same mass 'm' touches the horizontal portion of the surface at the ground. The co-efficient of friction between the plank and the sphere is mu and that between the plank and the ground is mu//4 . Find the work done by the friction force between the plank and the ground till the sphere starts pure rolling on the plank. Neglect the height of the plank.