Question

A bullet is fired in a horizontal direction with a muzzle velocity of 300m/s. In absence of air resistance, how far will it have dropped in traveling horizontal distance of 20m

Answer 1

The equations of motion of a bullet

$$x=v_0t\\ y=gt^2$$

Hence

$$y=gx^2/v_0^2=9.8*20^2/300^2\\ =0.044\:\rm m=4.4\: cm$$