Q 12-03-140JEE MainJEE Main 2023 (11 Apr, Shift 2)Easy
Two identical cells each of emf $1.5\ \text{V}$ are connected in series across a $10\ \Omega$ resistance. An ideal voltmeter connected across $10\ \Omega$ resistance reads $1.5\ \text{V}$. The internal resistance of each cell is ______ $\Omega$.
Numerical value type. Enter your answer.
Answer: 5
$I=\dfrac{1.5}{10}=0.15\ \text{A}=\dfrac{3}{10+2r}\Rightarrow10+2r=20\Rightarrow r=5\ \Omega$.
Solution by Sreeraj P, M.Sc Physics