# Area of Airfoil cross-section

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Not really sure if this thread belongs here but im supposed to figure out the radius of gyration, section modulus, and Q values at the neutral axis for this symmetric wing cross section. The only problem is that im not even really sure how to find the area of the cross section. i know that it'll be ∫(f(x)-g(x)) dx from 0-1 (pretty much the only hint that we are given is that the cross section can "fit perfectly in a 1in x 1in box) but how i even find f(x) and g(x) is beyond me.

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Poster has been reminded to watch for misplaced homework threads, and not to do the student's homework for them.
There is a high chance for my answer to be wrong.If its right, by solving the equatuon with the boundary condition will give you the curve(refer the image).
If X axis in the diagram is your neutral axis then it is better to find x as a function of y by using the same boundary condition.(To calculate 2nd moment of area about the x axis). #### Attachments

Last edited:
Klystron
Gold Member
Alec, for future aerodynamic calculations consider determining the mean aerodynamic chord (MAC) of the wing section under study.
https://en.wikipedia.org/wiki/Chord_(aeronautics)

Before digital computers became common, aircraft engineers adopted many terms and techniques from boat building including chords.