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x14ace
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Homework Statement
The problem I'm stuck on is to come up with an equation which will model the path of the projectile in an xy-plane.
We are given:
r(t)={ [(v0cos(θ))t], [h+(v0sin(θ))t-(½)gt2] }
v0=100 ft/s
θ=60°
h=4 ft
so basically,
r(t)={[100cos(60)t], [4+100sin(60)t-16t2]}
Homework Equations
I know that:
x=rcosθ
y=rsinθ
tanθ=y/x
The Attempt at a Solution
I tried to get the t out for both components.
x=100cos(60)t
x=50t
t=x/50
y=4+100sin(60)t-16t2
y=4+86.6t-16t2
I used the quadratic equation and ended up with
t(0)=(-86.6±88.1)/8 =-21.83, 0.1875
I thought that when I solved for the t's and set them equal to each other, I would get an equation in xy coordinates but I'm not sure where to go from here.
I also tried to use x=rcosθ
since x=50t,
50t=rcos(60)
r=100t
x2+y2=r2
so (50t)2+y2=(100t)2
y2ends up equalling 7500t2
and I'm back to being stuck.