I am having the hardest time getting my range to match (at least I think they should). I used two range equations for the same problem as demonstrated below. I did it both ways to check my answer, and they are different. I was hoping you could tell me where I went wrong...I think my time of flight is incorrect.(adsbygoogle = window.adsbygoogle || []).push({});

v_0=105m/s

h=125m

Θ=37degrees

v_oy=63.19m/s (105m/s sin37)

v_ox=83.86m/s (105m/s cos37)

For my time of flight I used the equation y = v_0yt - 1/2gt^2 - h

Plugging in the numbers I get y = 63.19t - 1/2(9.8m/s)t^2 - 125

Rearranging the equation for quadratic, -4.9t^2 + 63.19t - 125

Then I use my quadratic formula and get

(-63.19(+-)39.28)/-9.8 thereby getting +2.349s and +10.45s. Neither of these fit when multiplied by my x of 83.86m/s. I get 196m and 876m.

For the problem I am checking the answer with is derived from the equation

R = v_o^2(sin2Θ)/g

So I get (105m/s)^2(sin2(37))/9.8m/s = 1081.41m

They don't match and they should, right?

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# Homework Help: Range Question

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