A box weighing 2000N is to be slowly slid through 20m on a straight track having coefficient of friction 0.2 with the box. (a) Find the work done by the person pulling the box with a chian at an angle theta with the horizontal. (b) Find the work done when the person has chosen a value of theta which ensures him the minimum magnitude of the force.

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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