Calculating Power Output of a Weightlifter

AI Thread Summary
To calculate the power output of a weightlifter lifting 250 kg over 2.00 m in 2.00 seconds, the correct formula for work is Work = mass x gravity x height (W = m*g*h). The gravitational force (g) is approximately 9.81 m/s², which must be included in the calculation. The correct work done is 250 kg x 9.81 m/s² x 2 m, resulting in 4905 J. Dividing this work by the time of 2 seconds gives a power output of 2.45 kW. Including the gravitational force is essential for accurate calculations.
lonlyincolleg
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Homework Statement


A weightlifter is able to lift 250 kg 2.00m, in 2.00s. What is his power output?


Homework Equations


W=M x N
P = W/Change t


The Attempt at a Solution


250 x 2 = 500 (I thought that this was work) so then I divided by time (2.00s) to get power. The answer is not right. It should be 2.45 kW. Please tell me what I am doing wrong.
 
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Work = m*g*h, you missed a "g" in there, so you are off by a factor of 9.81
 
I got it. thank you!
 

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