Calculating Work Done on Karen by Woodley Park Station Escalator

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AI Thread Summary
Karen, with a mass of 54 kg, rides the escalator at Woodley Park Station, which has an inclination of 29.4 degrees and a length of 59.5 m. The gravitational force acting on her is calculated as 529.2 N. The work done by the escalator is computed using the formula W = F * x * cos(theta), resulting in approximately 15,457.28 J. There is a discussion about the accuracy of using rounded values in calculations, particularly regarding the angle used in the force calculation. The final answer is confirmed to be correct, with a note on the importance of precision in such calculations.
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Homework Statement


Karen has a mass of 54 kg as she rides the
up escalator at Woodley Park Station of the
Washington D.C. Metro. Karen rode a dis-
tance of 59:5 m, the longest escalator in the
free world.
The acceleration of gravity is 9:8 m=s2 :
How much work did the escalator do on
Karen if it has an inclination of 29:4±? Answer
in units of J.


Homework Equations


W=F*x*cos(theta)
where F= force, x is displacement and theta is the angle between the 2


The Attempt at a Solution


I first drew a force diagram. And used it to figure out this:
mg=529.2N
F=529.2*cos60.6=259.786N <-force of escalator
Next i plugged it into the Work equation:
the angle between the displacement and force is 0, so cos(theta)=1:
W=259.786*59.5*1=15457.28285J

is this right? I just need a confirmation, because I can't afford to get this wrong. Ty in advance
 
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looks good!
 
but using 60 instead of the exact value makes your answer inaccurate
 
60? for:
F=529.2*cos60.6=259.786N <-force of escalator
 
haha, sorry, I didn't see the .6
 
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