Q 12-03-148JEE MainJEE Main 2023 (8 Apr, Shift 2)Medium
The equivalent resistance between $A$ and $B$ as shown in figure is
Answer: (B) $5\ \text{k}\Omega$
The top wire makes $D$ the same node as $A$, and the bottom wire makes $C$ the same node as $B$. Then each resistor lies directly between $A$ and $B$:
$$\frac1R=\frac1{20}+\frac1{20}+\frac1{10}=\frac{4}{20}\ \Rightarrow\ R=5\ \text{k}\Omega$$
Solution by Sreeraj P, M.Sc Physics