In parallel circuits all of the components will receive the same potential difference as that provided by the cell, so for example in our previous circuit which provided a potential difference of 12 V, every loop in the circuit will receive a potential difference across it of 12 V.


In the circuit shown above, which is identical to the previous one (except for the fact that all of the individual switches have been taken out, leaving just the master one in) the three identical bulbs would receive the same potential difference and would therefore shine with the same brilliance as each other. Obviously if any of the lamps were rated differently they would be dimmer or brighter and could possibly even blow.


Potential difference in parallel circuits can be shown by the simple equation below: