The Zero Gravity Research Facility at the NASA Lewis Re- search Center includes a 145-m drop tower. This is an evacuated vertical tower through which, among other possibilities, a 1-m-diameter sphere containing an experimental package can be dropped. (a) For how long is the experimental package in free fall? (b) What is its speed at the bottom of the tower? (c) At the bottom of the tower, the sphere experiences an average acceleration of 25g as its speed is reduced to zero. Through what distance does it travel in coming to rest?

Three identical balls are placed on a frictionless horizontal surface touching each other. They stick to each other because of adhesive. Another ball of same radius and mass m is placed over the void created by the three balls. Find the forces applied by the balls kept on the floor to each other if the system remains in equilibrium.

A car loaded with water having total mass 1000 kg moves on a straight horizontal Road starting from rest under the action of a force of 100 Newton. The water spills throw a small hole in the bottom at a rate of 0.1 KG per second the velocity of cart after 300 seconds is nearly.

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