Q 12-03-142JEE MainJEE Main 2023 (12 Apr, Shift 1)Medium
The current flowing through a conductor connected across a source is $2\ \text{A}$ and $1.2\ \text{A}$ at $0^\circ\text{C}$ and $100^\circ\text{C}$ respectively. The current flowing through the conductor at $50^\circ\text{C}$ will be ______ $\times10^2$ mA.
Numerical value type. Enter your answer.
Answer: 15
$R\propto\dfrac1I$ and $R=R_0(1+\alpha T)$: $\dfrac{2}{1.2}=1+100\alpha\Rightarrow\alpha=\dfrac1{150}\ ^\circ\text{C}^{-1}$.
At $50^\circ\text{C}$: $R=R_0\left(1+\dfrac13\right)=\dfrac43R_0$, so $I=\dfrac{2}{4/3}=1.5\ \text{A}=15\times10^2\ \text{mA}$.
Solution by Sreeraj P, M.Sc Physics