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For two identical cells each having emf $E$ and internal resistance $r$, the current through an external resistor of $6\,\Omega$ is the same when the cells are connected in series as well as in parallel. The value of the internal resistance $r$ is ________ $\Omega$.

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When currents are equal in series and parallel cell combinations, equate the current expressions directly to find internal resistance.

Updated On: Apr 2, 2026

$9$
$3$
$6$
$4$

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The Correct Option is B

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For two identical cells each having emf \(E\) and internal resistance \(r\), the current through an external resistor of \(6\,\Omega\) is the same when the cells are connected in series as well as in parallel. The value of the internal resistance \(r\) is ________ \(\Omega\).

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The Correct Option is B

Solution and Explanation

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