Question

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

Answer 1

Hint Electromotive force or e.m.f is defined as the electric potential produced by either an electrochemical cell or by changing the magnetic field. The potential difference between two points is defined as the amount of work done in moving a unit charge from one point to another.

Complete Step by step solution
Differences between e.m.f and potential difference are:

E.m.f. (Electromotive Force)	Potential difference
e.m.f. exists even after the circuit is broken.	The potential difference doesn’t exist after the circuit is broken.
e.m.f. does not depend on the resistance of circuits.	It depends on the resistance between the two potential points.
It has a greater value than the terminal voltage of the cell in a closed circuit.	Always lesser than the e.m.f of the cell used
It causes the current to flow in a circuit connected to the given cell.	Caused due to flow of current in a circuit

Additional information Electromotive force is the electrical activity produced by a non-electrical source or a chemical source. Devices provide an emf by converting other forms of energy (chemical energy) into electrical energy, such as batteries and cells. In the case of generator energy from a fuel like petrol is converted to electrical energy.

Note Electromotive force is the potential of a cell before the circuit is closed whereas the potential difference is the difference in potential between two points. This difference in potential is caused due to a source of e.m.f such as a cell or battery. This causes electrons to flow, which means it causes current to flow.