Posted by demi on .
A rifle is used to shoot twice at a target, using identical cartridges. The first time, the rifle is aimed parallel to the ground and directly at the center of the bull's eye. The bullet strikes the target at a distance of HA below the center, however. The second time, the rifle is similarly aimed, but from 3.5 times the distance from the target. This time the bullet strikes the target a distance of HB below the center. Find the ratio of HB/HA.

physics 
Anonymous,
assuming no air friction, the horizontal speed of the bullet is the same everywhere in the problem
therefore the time in B is twice as lng as in A
the bullet therefore falls 3.5 times as long
h = .5 g t^2
hA = .5 g t^2
hB = .5 g (3.5 t)^2
3.5^2 t^2/t^2 = 12.25 times as far