Ok :rofl: ,(adsbygoogle = window.adsbygoogle || []).push({});

I had to test my maximum vertical jump. I did three trials and here's what I got:

-Maximum standing height (ie without jumping reaching with one hand) = 221.5 cm

-Maximum jumping height with one hand (best of three) = 270 cm

-Net Height 270-221.5 cm = 48.5 cm, 0.485m

My weight: 68 kg

And now the physics I had to do:

1)Calculate maximum potential gravitational energy during jump.

So PE=mgh

=(68kg)(9.81)(0.485m)

=323.5 J

2)Calculate work done

W=F x d

= 68kg(9.81)(0.485m)

=323.5 J

3) Calculate the average force required to jump this high if you apply the force over a distance of 0.5 meters. <<<I don't get what this is trying to ask>>>

4) Calculate power produced to jump this high if force applied for 0.5secs.

P=work/t

=323.5j/0.5 s

=647 Watts

5)Calculate your vertical velocity half way back to the ground.

So that distance is is just half of 48.5 cm?? or 24.25 cm

323.5 J=mgh +1/2mv^2

323.5J= 68(9.81)(0.2425m) +1/2(68kg)v^2

so, 161.7(2)/68kg=v^2

4.76=v^2

**v=2.18 m/s??

6)Calculate your vertical velocity the instant before you land.

So the instand I land is when the h=0.01m or the smallest distance before hitting the ground.

323.5=68(9.81)(0.01m)+1/2(68)v^2

317(2)/68=v^2

9.32=v^2

**v=3.05 m/s?

7) Calculate the average force required to absorb the energy of your landing if you take 0.25 meters to stop.

<<<I also don't get what this one>>>

Alright thanks guys. :tongue:

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# Homework Help: Vertical Jump Test and physics! Check My Work

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