An iron ball at 40°C is dropped in a mug containing water at 100°C. The heat will i. Flow from iron ball to water. Ii. Not flow from iron ball to water or from water to iron ball. Iii. Flowfrom water to iron ball. Iv. Increase the temperature of both.

The man of mass m1 and the woman of mass m2 are standing on opposite ends of the platform of mass m0 which moves with negligible friction and is initially at rest with s = 0. the man and woman begin to approach each other. derive an expression for the displacement s of the platform when the two meet in terms of the displacement x1 of the man relative to the platform.