# prove work energy theorem

Work energy theorem states that the change in kinetic energy of an object is equal to the net work done on it by the net force. From the third equation of motion: as = (v 2 - v 0 2)/2 W = 1/2m(v 2 - v 0 2) = KE f - KE i. The work done on a body by a force is equal to the increase in the kinetic energy of the body. Share with your friends. A constant force will produce constant acceleration. Hence the work done by friction is negative. Note: If the speed of an object increases ( v f > v i) W > 0. Sorry!, This page is not available for now to bookmark. In this graph, x-axis is taken as displacement, and y-axis is force. Do up vote if u find this answer helpful. So let’s try to use work-energy theorem. Share 4. Energy Theorem. This is work done by a variable force. Consider a body having mass 0.5 kg, and travelling in a straight line. 10th. Since F= ma, and velocity is the rate of change displacement over time rate, we can write the above equation as. A graphical approach to this would be finding the area between F(x) and x from $$x_i$$  to $$x_f$$ . 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