Question

What is emf ? What is the importance of emf ?

Answer 1

is the voltage developed by any source of electrical energy such as a batteryor dynamo. It is generally defined as the electrical potential for a source in a circuit A device that converts other forms of energy to electrical energy supplies an emf to a circuit
it's importance is In electromagnetic induction, emf can be defined around a closed loop as the electromagnetic workthat would be done on a charge if it travels once around that loop

Answer 2

HEY MATE HERE IS YOUR ANSWER:-

EMF of a cell is the potential difference between two electrodes of the cell when the circuit is opened.

HOPE IT HELPS