Work Energy Problems With Friction

Conservation of energy in which the sum of the initial kinetic and potential energies is equal to the sum of the final kinetic and potential energy is technically.

Work energy problems with friction.

A mass m 5 kg starts its motion at point a see figure at a height h a 2 m with a speed v a 20 m s. The work energy theorem states that the change in kinetic energy of an object is equal to the work done on that object but this equation is only valid for frictionless processes. The first problem asks you to c. A 2 kg object is being pushed by a horizontal force f along a horizontal frictionless air table.

There is no friction or air resistance so wnc 0. So when the force is going in the opposite direction as the distance your work is negative. So another way of thinking of this problem is energy initial is equal to or you could say the energy initial plus the negative work of friction right. The coefficient of friction between the pitcher and the counter top is 0 28.

Determine the work done by pete on the pitcher during the 48 cm push. Determine the total work done upon the pitcher. A 2kg crate rests on the floor. Determine the value of the work of the friction force between points a and b.

Work and work energy theorem. The problem involves a change in height and speed and has a spring so we apply the generalized work energy theorem wnc δe. Both the engine and friction do work on the car. How much work is required to move it at constant speed a 3m along the floor against a friction force of 4n b 3m along a frictionless air table c 3m vertically.

The whole time friction is acting against the distance. The spring is compressed initially so it loses spring. Determine the work done by friction upon the pitcher. The work energy theorem states that the net amount of work done on an object is equal to the object s final kinetic energy minus its initial kinetic energy.

The sum of that work must be equal to the change in the car s kinetic energy.