JEE Main 2023 — Rotational Motion Question with Solution

A uniform disc of mass $0.5\mathrm{kg}$ and radius $r$ is projected with velocity $18\mathrm{m}/\mathrm{s}$ at $\mathrm{t}=0$ s on a rough horizontal surface. It starts off with a purely sliding motion at $\mathrm{t}=0\mathrm{s}$. After $2\mathrm{s}$ it acquires a purely rolling motion (see figure). The total kinetic energy of the disc after $2\mathrm{s}$ will be __________ $\mathrm{J}$ (given, coefficient of friction is $0.3$ and $g=10\mathrm{m}/{\mathrm{s}}^2$ ).