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प्रश्न
Plot a graph showing variation of voltage vs the current drawn from the cell. How can one get information from this plot about the emf of the cell and its internal resistance?
उत्तर
Variation of voltage vs the current drawn from the cell shown below:
\[V = E - Ir\]
\[At, I = 0\]
\[V = E\]
\[\text { and }\]
\[r = \frac{E - V}{I}\]
The slope of the graph give the value of internal resistance and intercept on Y-axis gives the emf of the cell.
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