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Question
Distinguish between emf and terminal voltage of a cell.
Solution
Emf | Terminal voltage |
It is the maximum potential difference that can be delivered by a cell when no current flows through the circuit. | It is the potential difference across the terminals of the load when the circuit is switched on and a current flows through it. |
It is represented by E and remains constant for a cell. | It is represented by V and depends on the internal resistance of the cell. |
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