a carpenter of mass 50 kg is standing on a weighing machine placed in a lift of mass 20 kg.

a light string is attached to the lift. the string passes over a smooth pulley and is attached to the lift and the other end is held by the carpenter.when carpenter keeps the lift moving upward with constant velocity, find-

​1. reading of the weighing machine

​2. net force on the man.

​3. net force on the weighing machine.

​4. tension of the string

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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