Question:
In a potentiometer experiment for measuring the emf of a cell, the null point is at 240 cm when we have a 500 Ω resistor in series with the cell and galvanometer. If the series resistance is reduced to half, then the null point will be at:
In a potentiometer experiment for measuring the emf of a cell, the null point is at 240 cm when we have a 500 Ω resistor in series with the cell and galvanometer. If the series resistance is reduced to half, then the null point will be at:
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Potentiometer measures emf directly; null point does not depend on series resistance.
Updated On: Apr 16, 2026
- 480 cm
- 240 cm
- 120 cm
- 60 cm
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The Correct Option is B
Solution and Explanation
Step 1: In potentiometer, null point is independent of series resistance.
Step 2: Therefore, null point remains at 240 cm.
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