Question

A cannon is placed on a 1m tall stand at the edge of a hill with a declination of 20 degrees and length of 200m. If fired at a velocity of 55m/s, find the angle theta such that the projectile hits exactly at the bottom of a hill.

Answer 1

Find the bottom of the hill using trigonometry.

The height of the cannon ball above ground will be given by

h = (hill height + 1m) + (55m/s)[sin 2] t - (1/2) (9.8 m/s^2) (t)^2

the x distance from the muzzle will be x = (55m/s) cos(@) t
which equals the x position of the bottom of the hill, x = 200 cos(20).

t is the time and @ is the angle.