Potential Difference is Energy Transferred per Charge Passed

• When an electrical charge goes through a change in potential difference, then energy is transferred

• Energy is supplied to the charge at the power source to ‘raise’ it through a potential

• The charge gives up this energy when it ‘falls’ through any potential drop in components elsewhere in the circuit.

• Formula=E = QV

• Energy Transferred= Charge flow x potential difference

• That means that a battery with a bigger pd will supply more energy to the circuit for every coulomb of charge which flows around it, because the charge is raised up ‘higher’ at the start

Power also depends on Current and Potential Difference

• As well as energy transferred in a given time, the power of an appliance can be found with

• Power=Potential Difference x Current P=VI

• You can also find the power if you don’t know the potential difference

• P=I(2)R