Answer:
Explanation: v = 40 m/s, H = 10m, g = 9.8 m/s2
H = (v * sinθ)^2 / 2g
H = v^2 * (sinθ)^2 / 2g
H = (40)^2 * (sinθ)^2 / 2g
H = 1600 * (sinθ)^2 / 2g
Cross multiply
2gH = 1600 * (sinθ)^2
2 * 9.8 * 10 = 1600 * (sinθ)^2
196 = 1600 * (sinθ)^2
Make (sinθ)^2 the subject of the formula
(sinθ)^2 = 196 / 1600
Take the square root of both sides
√(sinθ)^2 = √( 196 / 1600)
sinθ = 0.35
θ = sin^-1(0.35)
θ = 20.48731511
Approx. 20.49
I hope this was helpful