Differences between E.M.F and Voltage (P.d)

Differences between E.M.F and Voltage (P.d)

The following are the difference between E.M.F and P.D.

• The name E.M.F at first sight implies that it is a force that causes current to flow.But this is not correct because it is not a forced but energy supplied to charge some active device such as battery.


• E.M.F maintains p.d. while p.d. cause current to flow.


• When we say that E.M.F of a device (e.g., a cell) is 3V it means that the device supplies energy of 3 joules to each coulomb of charge. When we say that a p.d. between point A and B of a circuit (suppose point A is at higher potential) is 3V, it means that each coulomb of charge will give up an energy of 3 joule in moving from A to B.