\(K=\frac{3}{2} k T\) ..... \((i)\)
Also momentum ( \(p\) ) is, \(p=\sqrt{2 m K}\) From eqn. \((i)\)
\(p=\sqrt{2 m \cdot \frac{3}{2} k T}=\sqrt{3 m k T}\)
Required de-Broglie wavelength is given as
\(\lambda=\frac{h}{p}=\frac{h}{\sqrt{3 m k T}}\)
(he $=1245 \mathrm{eVnm}, \mathrm{e}=1.6 \times 10^{-19} \mathrm{C}$ આપેલ છે.)