Explanation

The bullet performs a horizontal journey of 100 cm with constant velocity of $1500 m/s$. The bullet also performs a vertical journey of h with zero initial velocity and downward acceleration g. $\therefore$ For horizontal journey, time (t) = Distance/Velocity $\therefore t = 100/1500 = 1/15 \text{sec}$ The bullet performs vertical journey for this time. For vertical journey, $h = ut + (1/2)gt^{2}$ $h = 0 + (1/2) \times 10 \times (1/15)^{2}$ or, $h = 20/9 cm = 2.2 cm$