In Bohr's atomic model, the electron is assumed to revolve in a circular orbit of radius 0.5 Å. If the speed of electron is 2.2 × 10? m/s, then the current associated with the electron will be _______ × 10?² mA. [Take π as 22/7]

$r_n=a_0{n}_2$

$\begin{array}{rr}& {\mathrm{r}}_1={\mathrm{a}}_0=5.3\times {10}^{-11}\mathrm{m}\\ & {\mathrm{r}}_3={\mathrm{a}}_0\left(3\right)2\\ & =5.3\times {10}^{-11}\times 9\\ & =4.77\text{?}\end{array}$

Density of nucleus is constant.

$\Delta E=hv\to \left(\frac{1}{n_2^2}-\frac{1}{n_1^2}\right)$

(1) n₁ = 3, n₂ = 2

    $\left(\frac{1}{2^2}-\frac{1}{3^2}\right)=\frac{9-4}{36}=\frac{5}{36}$         

(2) n₁ = 4, n₂ = 3

$\left(\frac{1}{3^2}-\frac{1}{4^2}\right)=\frac{16-9}{144}=\frac{7}{144}$        

(3) n₁ = 2, n₂ = 1

$\left(\frac{1}{1^2}-\frac{1}{2^2}\right)=\frac{4-1}{4}=\frac{3}{4}$  

(4) n₁ = 5, n₂ = 4

$\left(\frac{1}{4^2}-\frac{1}{5^2}\right)=\frac{25-16}{400}=\frac{9}{400}$