Question

Dual behaviour of matter proposed by de Broglie led to the discovery of electron microscope often used for the highly magnified images of biological molecules and other type of material. If the velocity of the electron in this microscope is 1.6 × 106 ms–1, calculate de Broglie wavelength associated with this electron.

Answer 1

From de Broglie's equation,
λ = $\frac{h}{mv}$
λ = $\frac{6.626 × 10^{-34}Js}{ (9.10939 × 10^{-31} kg)(1.6 × 10^6 ms^{- 1})}$
= 4.55 × 10-10m
λ = 455 pm
∴ de Broglie's wavelength associated with the electron is 455 pm.