When an external resistance of 5 Ω is connected across terminals of a cell, a current of 0.25 A flows through it. When the 5 Ω resistor is replaced by a 2 Ω resistor, a current of 0.5 A flows through it. The internal resistance of the cell is ______ Ω.

1. Concept. E=I(R+r) with the same E and r for both loads. Step 1. Equate. 0.25(5+r)=0.5(2+r)1.25+0.25r=1+0.5r. Answer. r=1 Ω.

Current Electricity question for JEE Main (JEE Main 2026 (5 Apr, Shift 2)), with solution

Q 12-03-053JEE MainJEE Main 2026 (5 Apr, Shift 2)Easy

When an external resistance of $5\ \Omega$ is connected across terminals of a cell, a current of $0.25$ A flows through it. When the $5\ \Omega$ resistor is replaced by a $2\ \Omega$ resistor, a current of $0.5$ A flows through it. The internal resistance of the cell is ______ $\Omega$.

Numerical value type. Enter your answer.

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Current Electricity question for JEE Main (JEE Main 2026 (5 Apr, Shift 2)), with solution

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