Surface area of a cylinder question

AI Thread Summary
The discussion revolves around calculating the height of a cylindrical space station with a specified surface area of 800 m². The formula used is 2πrh, where the radius is given as 399.97 m. Initially, the calculated height was 0.318 m, which seemed unreasonably low, leading to confusion about whether the surface area should be squared. Clarification revealed that 800 m² is correct, and the height calculation is accurate as stated. The participant acknowledges the mix-up and expresses gratitude for the clarification.
Asphyxiated
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Homework Statement



This is actually for my Physics 211 class but the question is very simple. We were asked to construct a cylindrical space station to specific parameters which are not important to the question. I know that my cylinder has a radius of 399.97m and a rotational period of 40.12 seconds to fit the given requirements. It also states that the space station must have a surface area equal to .8 km^2 or 800 m^2. The surface area of a cylinder (minus the top and the bottom which we are to ignore) is:

2 \pi r h = A

That is:

2 \pi (399.97) h = 800 m^{2}

h = \frac {800 m^{2}}{2 \pi (399.97)} = .318 m

which is only about a foot... Am I looking at this wrong is is the height seriously suppose to be .318 meters? Is the 800 suppose to be squared as well by chance? lol cause if it was i get a height of 254.66 m which sounds a whole lot better to me.

Please note that I know that the other numbers I am using are 100% correct, i have confirmed the with my teacher, i just never thought to ask about the height but it turns out I squared 800 before and got the more reasonable (to me) 254.66 meters... Now that I am writing the lab it seems that it should just be 800 and now the height is only .318m! lol, let me know what you think.

Thanks!
 
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Asphyxiated: Remember 1km = 1000 m, therefore 1 km^2 = 1 square km
1 km^2 = 1000 m x 1000 m

The SA of the station is then 0.8 km^2 = 800000 sq. m
 
Asphyxiated said:
Is the 800 suppose to be squared as well by chance?

Yep :wink:

1km2=10002m2=1,000,000m2

edit: sorry I mistakenly wrote 800,000 when I was meant to write 800^2=640,000
 
Last edited:
Ok good lol, I am not sure why I was second guessing myself the first time. Thanks for clearing that issue up. I think studying for my calc II finals have thrown me off on my physics stuff.

Thanks much though!
 
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