Kinematics

A projectile is fired
from the surface of level ground at an angle *φ*_{o} above the
horizontal.

(a) Show that the elevation angle *θ* of the highest point
as seen from

the launch point is related to *φ*_{o} by tan *θ*
= (1/2) tan *φ*_{o}.

*(b)
*Calculate *θ* for *φ*_{o}
= 45°.