Potential is "electrical pressure" or "voltage". If two isolated pieces of metal are both electrically balanced ( both at zero volts ) then the potential difference between them is
0 - 0 = 0V
If one piece is charged a little bit positive (by removing a few electrons from it) it might raise its voltage or potential to say +2 Volts, and if the other piece has rather more electrons removed from it, then its potential will rise even more, to say 8 Volts. The Potential Difference (p.d.) will then equal 8V - 2V = 6V.
If one piece of metal has a given number of electrons taken away to make it say +5V and the other has enough electrons added to it to make it equal to 5V negative (-5V), then the p.d. is (+5V) - (-5V) = 5V + 5V = 10V.
If two points with a potential difference between them are connected together via a conductor (metal wire) then the potential difference (or electrical pressure in other words) will force electrons to move from the more negative towards the more positive, and this is "conventionally" said to constitute an electrical "current flow" from Positive to Negative (yes I know that's daft since it's the electrons that are actually flowing from Negative to Positive - but the concept was postulated before electrons were discovered and we are still stuck with it)
The size of the current ( I ) in Amps will be directly proportional to the Voltage ( V ) or p.d. and inversely proportional to the resistance of the conductor ( R ) in ohms ( Ω )
i.e. Current = Potential Difference divided by Resistance or I = V / R
Hope that helps - Majikthise.
It's the amount of energy per unit charge. Think of it as distance over time, that gives you the speed right? So if it''s 70 kilometers per hour, its 70km/h. Its the same concept, except it's in energy and charge.
The amount of energy per unit charge needed to move a charged particle from a reference point to a designated point in a static electric field...basically like voltage.
wow thats one long definition
nicely detailed thanx :)