Question

Write four points of difference between e.m.f. (Electromotive Force) and Potential difference.

Answer 1

Hint : An e.m.f. is generated by a battery or a cell due to its tendency to cause current to flow in a circuit. The potential difference is a practical quantity that defines the tendency of current to flow from one point to another.

Complete step by step answer
The four points of difference between the electromotive force and the potential difference are as follows:

Electromotive Force (e.m.f.)	Potential difference
e.m.f. depends on the cell or battery and exists even if the circuit is broken or if the switch in the circuit is open.	The potential difference exists between two points in a circuit when current is flowing through it and will not exist when the circuit is broken
e.m.f does not depend on the resistance in the circuit since it is a property of the cell/battery	The potential difference depends on the resistance between points in the circuit
e.m.f is always greater than the terminal voltage of a closed-circuit since it does not take into account the potential drop across the internal resistance of the battery	It is always less than e.m.f. of the cell/battery used since it takes into account all resistances in the circuit
It is the cause of the flow of current in a circuit connected to a cell or battery	It is generated because of the flow of current between two points in a circuit

Note
The potential difference across a practical cell or battery is less than its e.m.f since there will be a potential drop across the internal resistance of the battery. E.m.f. and potential difference have the same units i.e. the same dimensional formula however they represent different behaviour of the circuit as we discussed above.