Answer:
4.097 s
Explanation:
The formula for ballistic motion usually used is ...
h(t) = -4.9t² +v₀t +s₀
where v₀ and s₀ are the initial vertical velocity and height, respectively. Here, we have v₀ = (35 m/s)sin(35°) and s₀ = 0. We want to solve for h(t) = 0.
0 = -4.9t² +35sin(35°)t = t(-4.9t +35sin(35°))
This is true for t=0 and for ...
t = 35sin(35°)/4.9 ≈ 4.09697 . . . seconds
It will take about 4.097 seconds for the projectile to reach the ground.
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Comment on the graph
Desmos has a setting option for angles in degrees. That is what we used here.