# Physics Topic: Work Energy Power

Show an understanding of the concept of work in terms of the product of a force and displacement in the direction of the force.

Calculate the work done in a number of situations including the work done by a gas which is expanding against a constant external pressure.

Give examples of energy in different forms, its conversion and conservation, and apply the principle of energy conservation to simple examples.

Derive, from the equations of motion, the formula K.E. = 1/2mv

^{2}.Recall and apply the formula K.E. = 1/2mv

^{2}.Distinguish between gravitational potential energy, electric potential energy and elastic potential energy.

Show an understanding and use the relationship between force and potential energy in a uniform field to solve problems.

Derive, from the defining equation

*W = Fs*, the formula*E*for potential energy changes near the Earthâ€™s surface._{p}= mghRecall and use the formula

*E*for potential energy changes near the Earthâ€™s surface._{p}= mghShow an appreciation for the implications of energy losses in practical devices and use the concept of efficiency to solve problems.

Define power as work done per unit time and derive power as the product of force and velocity.