Ok, I am having some trouble with the maths regarding Bohr Theory. I understand that the orbit radius is r=n^2xa0 where a0=0.0529 and that the wavelength for an electron with l=0 (circular orbit), is λ=2∏r so for n=1, λ=6.28a0. So, following the same maths, for n=2, I get λ=2x∏x2^2=8∏a0. However, according to http://hyperphysics.phy-astr.gsu.edu/hbase/bohr.html#c5, The answer is 4∏a0, which means that n is not squared. Can anyone please explain whether or not n is squared to work out the orbital radius?