why don't textbooks ever give the stress/tension of the spokes on a wheel? How would you find this?
I am not sure if there are any textbooks giving this questions. But it can be calculated. At least you need the diameter of the rim, the number of spokes, the maximum force the axis can tolerate, the way they are assembled etc... For normal spokes (not the hard ones), there are only tension forces, not stress.
You can read this in wiki : http://en.wikipedia.org/wiki/Spoke
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