For electron moving in nth orbit of H-atom the angular velocity is proportional to

Ans: (d)

Sol: $\large T = \frac{2\pi r}{v}$

$ r \propto \frac{n^2}{Z}$ and $ v \propto \frac{Z}{n}$

$ T \propto \frac{n^3}{Z^2}$

$\omega = \frac{2\pi}{T} \propto \frac{1}{n^3}$