Simple equation to calculate my initial velocity

AI Thread Summary
To calculate initial velocity when jumping, the equation v = sqrt(2gh) can be used, where h is the jump height. For a 1-meter jump, the initial velocity is approximately 4.5 m/s. If weight decreases from 91kg to 81kg, the jump height can increase by about 10%, reaching approximately 1.1 meters. The discussion emphasizes that understanding bodily physics often requires practical experimentation rather than just theoretical equations. Overall, applying basic laws of motion can help estimate jump dynamics effectively.
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I am looking for a simple equation to calculate my initial velocity when I jump in layman's terms. For instance...if I weigh 91kg and jump 1 meter...what is my initial velocity and what would my maximum jump height be if I weighed 81kg? This is probably something I missed in freshman physics...but I was a business major and not too bright!
 
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the kinetic .5mv*v goes into Potential mgh
v*v=2gh
v=sqrt(20h)
so in ur example where h=1 then v is about 4.5m/s

if you lost 10kgs and had the same jump force you would go 91/81 higher, approx 1.1m
 
Your initial velocity is zero and your jump height is undetermined at this point. Bodily physics is best understood by experiment, applying basic laws of motion will not ever give you a useful model.

Do you mean maximum velocity? That can be determined easily. If you jump up a meter you jump down a meter and applying a basic law (s = ut + at^2/2) we have 1m = gt^2/2 => t = sqrt(2/g) seconds (double it for your total time in the air when jumping a meter).

The above poster is completely correct.

Although at 91kg, you are either an incredibly ripped individual or an alternative bodily form. In the latter case I recommend intense cycling.
 
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