Ok, here's the problem. I am evaluating multiple crossbows to predict the changes caused by various arrow weights. The original arrow mass and velocities are available. I input the two formula's: KE = 1/2MV^2 and MO = MV and solve for each, and then use those results with new arrow weights to solve for the new velocities. My problem is that I get different results.(adsbygoogle = window.adsbygoogle || []).push({});

Which should prove to be the most accurate predictor and why?

I know the results will not be pure because they don't include friction and other variables, but just based on the formula's above I was expecting closer results.

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# KE vs Momentum as a standard

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