Suppose that you were called upon to give some advice to a lawyer concerning the physics involved in one of her cases The question is whether a driver was exceeding a 30-mi/h speed limit before he made an emergency stop, brakes locked and wheels sliding. The length of skid marks on the road was 19.2 ft. The police officer made the assumption that the maxi mum deceleration of the car would not exceed the acceleration of a freely falling body (= 32 ft/s²) and did not give the driver a ticket. Was the driver speeding? Explain.

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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