Question

Calculate the de Broglie wavelength of a non-relativistic proton with a kinetic energy of 10 eV.

Answer 1

Given:

$E_k=10\:\rm eV=1.6*10^{-18}\: J$

The de Broglie wavelength is given by

$$\lambda=\frac{h}{p}=\frac{h}{\sqrt{2mE_k}}$$ $$\lambda=\frac{6.67*10^{-34}}{\sqrt{2*1.67*10^{-27}*1.6*10^{-18}}}=9.1*10^{-12}\:\rm m$$