As per Bohr's postulate,

$ $$\begin{array}{l} m v r=\frac{n h}{2 \pi} \quad \text { So, } v=\frac{n h}{2 \pi m r} \\ \mathrm{KE}=\frac{1}{2} m v^{2} \quad \text { So, } \mathrm{KE}=\frac{1}{2} m\left(\frac{n h}{2 \pi m r}\right)^{2} \end{array}$$ $

$\text { Since, } r=\frac{a_{\mathrm{o}} \times n^{2}}{z}$

So, for $2^{\text {nd }}$ Bohr orbit

$ $$\begin{array}{l} r=\frac{a_{\mathrm{o}} \times 2^{2}}{1}=4 a_{\mathrm{o}} \\ \mathrm{KE}=\frac{1}{2} m\left(\frac{2^{2} h^{2}}{4 \pi^{2} m^{2} \times\left(4 a_{\mathrm{o}}\right)^{2}}\right)=\frac{h^{2}}{32 \pi^{2} m a_{\mathrm{o}}^{2}} \end{array}$$ $