De-Broglie waves explain about the nature of the wave related to the particle. Einstein explained the momentum (p) of a photon with the given formula
c = speed of light.
The energy (E) of a photon is given as
E = mc2,
m =hλ/c2 ————-(2)
h= Planck’s constant(6.62607015×10−34 Js)
λ = wavelength of light
substituting equation (2) in equation (1) we get
De Broglie Wavelength Formula is used to calculate the wavelength and momentum in any given problems based on this concept.
Question 1: Find the wavelength of an electron moving with a speed of ms-1.
Velocity of the electron, v =2×106 ms-1
Mass of electron, m =9.1×10-31 Kg
Planck’s Constant, h = 6.62607015×10−34 Js
The de-Broglie wavelength is given by λ = h/mv
= 6.62607015×10−34 /(2×106)(9.1×10-31 )
λ = 0.364×109m