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CaptainSMASH
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Homework Statement
The fireman wishes to direct the flow of water from his hose to the fire at B.
Determine two possible angles θ1 and θ2 at which this can be done. Water flows from the hose at v = 55 ft/s.
There is no air friction.
Homework Equations
v = v0 + at
x = x0 + vt
v2 = v[tex]^{2}_{0}[/tex] + 2ax
The Attempt at a Solution
Going to try and find the first angle (below the x-axis).
Components of the velocity:
Vx = 55cosθ1
Vy = 55sinθ1
Horizontal velocity is constant therefore we can find an equation for time:
x = x0 + vt
35 = 0 + (55cosθ1)t
t = 35[tex]/[/tex]55cosθ1
Sub this into an equation for vertical velocity to find v final:
v = v0 + at
v = 55sinθ1 + (-32.174)(35[tex]/[/tex]55cosθ1)
Sub this velocity into another equation for vertical velocity:
v2 = v[tex]^{2}_{0}[/tex] + 2ax
v= v0 + [tex]\sqrt{2ax}[/tex]
(55sinθ1 + (-32.174)(35[tex]/[/tex]55cosθ1)) = 55sinθ1 + [tex]\sqrt{2(-32.174)(-20)}[/tex]
...use algebra to find the angle
I'm not sure if this gives the right answer for the first angle, I hope it does, and I'm unsure as to how to get the second angle. Do I break the question for θ2 into two parts? One equation for the vertical rise and then a second for the fall? I've been figuring this question out more and more as I typed this out (I hope) but it's been bugging me since yesterday, I'm hoping to get some assurance / help from you guys.
Thanks in advance.
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