Q 12-03-101JEE MainJEE Main 2024 (9 Apr, Shift 2)Medium
To determine the resistance ($R$) of a wire, a circuit is designed below. The $V$–$I$ characteristic curve for this circuit is plotted for the voltmeter and the ammeter readings as shown in the figure. The value of $R$ is ______ $\Omega$.
Numerical value type. Enter your answer.
Answer: 2500
From the graph, $\dfrac VI = \dfrac{8\ \text{V}}{4\ \text{mA}} = 2\ \text{k}\Omega$. This is the resistance of $R$ in parallel with $10\ \text{k}\Omega$:
$$\frac{10R}{10 + R} = 2 \;\Rightarrow\; 8R = 20 \;\Rightarrow\; R = 2.5\ \text{k}\Omega = 2500\ \Omega$$
Solution by Sreeraj P, M.Sc Physics