# The KE of the electron in an orbit of radius r in hydrogen atom is : (e = electronic charge)

$\frac{{e}^{2}}{{r}^{2}}$

$\frac{{e}^{2}}{2r}$

$\frac{{e}^{2}}{r}$

$\frac{{e}^{2}}{2{r}^{2}}$

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