Physics Question from JEE Main 2026 · 22 January, Shift 1

$XPQY$ is a vertical smooth long loop having a total resistance $R$, where $PX$ is parallel to $QY$ and the separation between them is $l$. A constant magnetic field $B$ perpendicular to the plane of the loop exists in the entire space. A rod $CD$ of length $L\,(L>l)$ and mass $m$ is made to slide down from rest under gravity as shown. The terminal speed acquired by the rod is _____ $\text{m/s}$.