Electrical Work

For the cell or power source to provide electrical energy to move electrons around the circuit and produce a flow of current, work must be done.The electrons must move a distance through a wire or conductor.The energy is carried by the charge as electrical potential energy and transferred to the components (the drift speed of the electrons, and so their kinetic energy, does not increase).Work done = energy transferred assuming no energy losses.The electric work is given as

W = Q V

The potential difference V is measured in volts, the electric charge Q in coulombs and the work done W is measured in joules.The e.m.f. (electromotive force) determines the amount of work an electron can do in an electrical circuit.The voltage source, such as a cell, battery or a power supply, provides the energy necessary to move electrons through the circuit. The higher the voltage, the greater the potential energy available to the electrons.When an electron moves from a point of higher potential to a point of lower potential, it loses potential energy and does work in the process.This work is used to perform useful tasks in the circuit, such as lighting a bulb or running an electric motor.