Question

In a projectile motion, if we measure the maximum
height h and horizontal range R
(1) How to get launch angle θ in terms of h and R
(2) A hobby rocket reaches a height of 72.3 m and lands 111 m from the launch point.What is the angle of launch?
What is the launch speed?

Answer 1

Let θ be the launch angle. Assume the ground is level. Let V be the launch speed.

R = 2 (V^2/g) sin θ cos θ

h = V^2 sin^2 θ / (2g)

R = 4 h cosθ/sin θ = 4 h cotθ

Check my thinkng.

Answer 2

21