JEE Main 2020 — Center of Mass Momentum and Collision Question with Solution

A block of mass $1.9 \mathrm{kg}$ is at rest at the edge of a table, of height 1 m. A bullet of mass $0.1 \mathrm{kg}$ collides with the block and sticks to it. If the velocity of the bullet is $20 \mathrm{m} {\mathrm{s}}^{-1}$ in the horizontal direction just before the collision then the kinetic energy just before the combined system strikes the floor, is [Take $\mathrm{g} = 10 \mathrm{m} {\mathrm{s}}^{-2}$. Assume there is no rotational motion and loss of energy after the collision is negligible.]