What is the Work Done by a Pitcher on a Baseball?

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The discussion revolves around calculating the work done by a pitcher when throwing a baseball. The initial calculation of 2.911 Joules was incorrect due to a failure to square the velocity in the kinetic energy formula. The correct formula is (1/2)mv^2, leading to a final answer of 119.351 Joules. Participants emphasized the importance of careful calculations and checking each step. The conversation highlights common mistakes in physics problems and the value of peer assistance in resolving them.
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A baseball leaves a pitcher's hand at a speed of 41.0 m/s. The mass of the baseball is 0.142 kg . Ignore air resistance. How much work has the pitcher done on the ball in throwing it?

I've tried using (1/2)mv^2, but there has got to be something weird going on, or i could just be using the wrong equation


thanks for any and all help :smile:
 
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i work it out and get the same thing every time i have tried it.
2.911 Joules is the answer I get, and WebAssign says that it is incorrect.
 
How are you getting that answer? Show what you did.
 
sorry

Sorry about not showing all the work.

I just take the givens: v=41.0 m/s m=0.142 kg

Then I plug it in to: \frac{m*v^2}{2}

\frac{41*0.142}{2}



That is the answer i come up with (2.911 Joules)
 
square your 41, boy!
 
duh. thanks i knew i was doing something completely dumb.
always got to forget the easy part.

right answer = 119.351 Joules

thanks a lot
 
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