I used to know this stuff. How fast will a rock be going after falling 5 seconds in a vacuum?(adsbygoogle = window.adsbygoogle || []).push({});

I'd also like to know the formula in simple terms.

At the gym on the hip sled we call it- you lay back and push up with feet and legs. The rack supporting the weights is at 45 degrees. If you have 500# on it how much force is required to move it? I'd also like the formula for this as well as the answer. I think it's a simple 50% or 250# because it's at 45 degrees but not sure. I just don't like these kids bragging to an old guy that they are pushing 500#!

hip sled here:

Thank you! Tregg

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# Acceleration of a rock

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