# Define emf and potential difference clearly.derive its formula

Aman Bansal
592 Points
12 years ago

Dear Sachin,

An emf is a source of electrical energy. Like a battery or a generator actively sources electrical flow.

Voltage is a measure of electrical potential between 2 points.

In looking at Ohms Law the sum around a loop is 0. The emf is the active element and the resistors "resist" the flow from the emf about the loop, hence voltage drops to account for the electrical energy supplied by the emf.

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Thanks

Aman Bansal

Vinayak Gupta
56 Points
12 years ago

emf is the max potential of a cell when no current is drawn from it.....voltage or potential difference is the potential of cell when current is drawn from it....its that simple.

E= V + IR.

V is potential remaining in cell. IR is potential drawn into the circuit.

kindly approve .