Question:medium
In the potentiometer, when the cell in the secondary circuit is shunted with \(4\,\Omega\) resistance, the balance is obtained at a length \(120\) cm of wire. Now when the same cell is shunted with \(12\,\Omega\) resistance, the balance is shifted to a length of \(180\) cm. The internal resistance of the cell is ________ \( \Omega \).
In the potentiometer, when the cell in the secondary circuit is shunted with \(4\,\Omega\) resistance, the balance is obtained at a length \(120\) cm of wire. Now when the same cell is shunted with \(12\,\Omega\) resistance, the balance is shifted to a length of \(180\) cm. The internal resistance of the cell is ________ \( \Omega \).
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In potentiometer problems, emf cancels out—always compare balance lengths using terminal voltage expressions.
Updated On: Mar 30, 2026
- \(12\)
- \(4\)
- \(6\)
- \(3\)
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The Correct Option is B
Solution and Explanation
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