POTENTIAL DIFFERENCE = IT IS DIFFERECE WHICH CREATE WHEN A BATTERY IS PUT IN A CIRCUIT . IT IS BETWEEN TWO ENDS OF OF A CURRENT CARRYING CONDUCTOR.
IT'S SI UNIT IS VOLT
FORMULA = V =I[CURRENT] R[RESISTANCE]
EMF REFERS TO:
The electromotive force is the maximum potential difference between two electrodes of a galvanic or voltaic cell. This quantity is related to the tendency for an element, a compound or an ion to acquire (i.e. gain) or release (loss) electrons..