Angular momentum (L) and radius (r) of a hydrogen atom are related as

Ans: (d)

Sol: $ \displaystyle r \propto \frac{n^2}{Z} $

$ \displaystyle r = constant \frac{n^2}{Z} $

$ \displaystyle n = c (r Z)^{1/2} $ ; where c = constant

Angular momentum , $ \displaystyle L = \frac{n h}{2\pi} $

$ \displaystyle L = c (r Z)^{1/2} \frac{h}{2\pi} $

Hence , L ∝ (r)^1/2