Answer
$ v = 2.19 \times 10^6 m/s $
Work Step by Step
We equate the Coulomb Force and centripetal force to find the speed of electron, since electron is traveling in its orbit. Solve for $ v$
$ \frac{k|e|^2}{r^2} = \frac{m_ev^2}{r}$
$ \frac{k|e|^2r}{m_er^2} =v^2$
$v= \sqrt{\frac{k|e|^2}{m_er} }$
Where $r = a_o = 5.292 \times 10^{-11} m$
$v= \sqrt{\frac{(8.99 \times 10^9 N . m^2 / C^2) (1.6 \times 10^{-19}C)^2}{(9.11 \times 10^{-31} kg )(5.292 \times 10^{-11} m)} }$
$ v = 2.19 \times 10^6 m/s $
