A box of mass 8.0 kg slides at a speed of 10 ms−1 across a smooth level floor before it
encounters a rough patch of length 3.0 m. The frictional force on the box due to this
part of the floor is 70 N. What is the speed of the box when it leaves this rough surface?
What length of the rough surface would bring the box completely 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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