A stiff spring has a force law given by F = – kx³. The work required to stretch the spring from the relaxed state x = 0 to the stretched length x = l is W0. In terms of W₀, how much work is required to extend the spring from the stretched length 1 to the length 2l?

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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