(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

An outfielder throws a baseball with an initial speed of 71.0 mi/h. Just before an infielder catches the ball at the same level, its speed is 85 ft/s. How much of the ball's mechanical energy is dissipated by air drag? (The weight of a baseball is 9 oz.) Answer is asked for in ft lb

2. Relevant equations

KE=KE+Energy lost to air drag 1/2mv^2= KE 5280ft=1mi 1h=3600s 1J=.738ft lb

3. The attempt at a solution

I converted 71mi/hr to m/s and got 31.7479m/s then I converted 85ft/s to m/s and got 25.91m/s. I then used KE= KE + energy lost to air drag and canceled out masses and got 168.18J= energy lost to drag. I then converted using the books conversion and got 124.12 ft lb. I have no idea where I when wrong. Thanks whoever helps.

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# Homework Help: Energy lost due to dissipation by air drag

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