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 wenjen Dec4-08 10:15 PM

Question Details:
Hi all. I was wondering if anyone could help me on this lab calculation thing.

Background Information:
So essentially the lab is jumping off a platform 3 times which is hooked up to a computer and measures Normal Force and Parallel Force which is Fy and Fx I believe respectively. Also, range is also measured using a measuring tape.

Objective/Data:

The data measured:
-Range (R)
-Fx
-Fy

The calculations needed to be found out:
-Initial angle for all 3 jumps
-Time
-Accelerationx
-Accelerationy

Data Measured:

Shallow Jump -
Range: 99cm (.99m)
Fx: -193.50N
Fy: 921.59N

Long Jump -
Range: 230cm (2.3m)
Fx: -312.20N
Fy: 1012.59N

High Jump -
Range: 96cm (.96m)
Fx: -108.40N
Fy: 1222.61N

Relevant Equations:
R = vo2 * sin2θ
Resultant Force = √Fx2 + Fy2
θ = Tan-1(Vy/Vx)

Attempted Solution:
First off, I am not sure if I am allowed to use my mass. Thus, fundamentally I am looking for a solution that doesn't involve mass if possible.

For the launch angle for the three jumps, I initially tried to manipulate the range equation but I couldn't figure out how to get the initial velocity. (t=0 at initial velocity right?)
Therefore, I used the third equation to find the launch angle using θ= Tan-1(Fy/Fx)
However, I am not sure if I am allowed to do that to find the launch angle?

For the time in flight. I believe I use Δy = Vot + .5gt2? Which becomes √2Δy/g = t.