Question

A cannon barrel is elevated at an angle of 45°. It fires a ball with a speed of 250 m/s. (For the following questions, ignore air resistance.)
(a) What height does the ball reach?
m

(b) How long is the ball in the air?
s

(c) What is the horizontal range of the cannon?
km

Answer 1

Vi = 250 sin 45 = 125 sqrt 2 initial up
u = 125 sqrt 2 forever horizontal

v = 125 sqrt 2 - 9.81 t
v at top = 0
9.81 t = 125 sqrt 2
solve for t at top

h = Vi t - 4.9 t^2
solve for h at top

total time in air = 2 t

d = 2 u t