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Question
State two differences between the e.m.f and terminal voltage of a cell.
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Solution
| e.m.f. of cell | Terminal voltage of cell | |
| 1 | The amount of work required to move a unit positive charge in the entire circuit both inside and outside the cell serves as the measurement. | The amount of work required to move a unit of positive charge outside the cell serves as the measurement. |
| 2 | It is the characteristic of the cell i.e., it does not depend on the amount of current drawn from the cell | It depends on the amount of current drawn from the cell. The more current drawn from the cell, the lower the terminal voltage. |
| 3 | It is equal to the terminal voltage when the cell is not in use and greater than the terminal voltage when the cell is in use. | It is equal to the cell's EMf when it is not in use, while it is less than the EMf when it is in use. |
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