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प्रश्न
Distinguish between emf and terminal voltage of a cell.
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उत्तर
| 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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संबंधित प्रश्न
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In a potentiometer arrangement for determining the emf of a cell, the balance point of the cell in open circuit is 350 cm. When a resistance of 9 Ω is used in the external circuit of the cell, the balance point shifts to 300 cm. Determine the internal resistance of the cell.
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- angular speed ω and
- length of the conductor l.
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