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प्रश्न
Explain why potential difference is always less than the e.m.f. of a cell?
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उत्तर
When a cell is in closed circuit, i.e., when current is drawn from it, then the potential difference between its electrodes is called the terminal voltage. It is always less than the e.m.f. because when charge flows in a circuit, some energy is spent in the flow of charge through the electrolyte of the cell.
संबंधित प्रश्न
The values of current I flowing in a given resistor for the corresponding values of potential difference V across the resistor are given below:
| I (amperes) | 0.5 | 1.0 | 2.0 | 3.0 | 4.0 |
| V (volts) | 1.6 | 3.4 | 6.7 | 10.2 | 13.2 |
Plot a graph between V and I and calculate the resistance of that resistor.
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Potential difference
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