Shots fired simultaneously from the top and foot of a vertical cliff at elevation of 30 degree and 60 degree respectively, strike an object simultaneously which is at height of 100 m. from the ground and at a horizontal distance of 200root3 m. from the cliff. Find the height of the cliff. Find the height of the cliff, the velocities of projection of the shots and the time taken by the shots to hit the object.(g=10m/sec.)

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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