Why are we not able to rotate a wheel by pulling or pushing along its radius?

Torques of equal magnitude are applied to a hollow cylinder and a solid sphere, both having the same mass and radius. The cylinder is free to rotate about its standard axis of symmetry, and the sphere is free to rotate about an axis passing through its centre. Which of the two will acquire a greater angular speed after a given time?

Why are we able to sip hot tea or milk faster from a saucer rather than a cup?

A diamagnetic substance is placed in the middle between two magnetic poles. If allowed to rotate, explain why the specimen comes to rest with its axis perpendicular to the field.

A solid cylinder of mass 20 kg rotates about its axis with angular speed 100 rad s-^1. The radius of the cylinder is 0.25 m. What is the kinetic energy associated with the rotation of the cylinder? What is the magnitude of angular momentum of the cylinder about its axis?

Explain why some of the leaves may get detached from a tree if we vigorously shake its branch.