1 A small sphere of mass 0.4 kg moves with constant speed \(1.5 \mathrm {~m} \mathrm {~s} ^ { - 1 }\) in a horizontal circle inside a smooth fixed hollow cylinder of diameter 0.6 m . The axis of the cylinder is vertical, and the sphere is in contact with both the horizontal base and the vertical curved surface of the cylinder.

1. Calculate the magnitude of the force exerted on the sphere by the vertical curved surface of the cylinder.
2. Hence show that the magnitude of the total force exerted on the sphere by the cylinder is 5 N .