Calculate Average Power Output of Man Climbing 1576 Steps

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To calculate the average power output of a man climbing 1576 steps, the correct approach involves using the weight instead of mass. The initial calculation of work done was based on mass, yielding 22,064J, which led to an average power output of 38.5 W. However, using weight (mass times gravitational acceleration) gives a work done of 216,447.84 J, resulting in an average power output of approximately 377.7 W. The discrepancy from the expected 380 W may stem from significant figures or rounding differences. Accurate calculations are crucial for precise results in physics problems.
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A man runs up 1576 steps in 9minutes 33sec. If the height gain of each step was 0.20m, and the mass of the runner was 70.0kgs, what was average power output during climb?
I used P=W/T & W=FD
W=70kg(1576)0.20=22,064J
P= 22,064J/573s = 38.5 W
answer given is380W
What am I missing?
 
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You used the man's mass. You should have used his weight.
 
so W=70kg(9.81)(.2)(1576)=216447.84
P=216447.84/573= 377.7W
Close but not 380W
Where is the discrepancy?
 
Significant digits?
 

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