please describe Davisson Germer experiment (X-rays, electrons).
grade 12 Modern Physics
Answers
Davisson Germer performed experiments during 1923-1927 related electrons at very high speeds bombarding crystals. They finally confirmed the de Broglie hypothesis of wave particle duality. These experiments proved that de Broglie’s equation for wavelength is right.
λ = h/p
A beam of electrons from a heated tungsten filament is accelerated through a high voltage potential. Electrons with a high kinetic energy hit a Nickel crystal. Si the electrons are scattered in different directions. Scattered electrons are observed. The diffraction pattern observed is similar to Bragg’s experiment on X-ray diffraction. Thus diffraction and not reflection of particles was observed.
It is deduced that electrons have too wave nature, as X-rays are waves. Only waves undergo diffraction. Particles do not undergo diffraction. They undergo reflection. The wavelength of the observed waves was almost same as calculated from de Broglie’s equation.
Davisson and Germer experiment:-
The main principle of this experiment is to prove that the x-rays showing wave character.
Davidson and germer experiment in 1927 conformed the De-broglie wavelength of duality . It also confirmed the see Broglie's wavelength equation.
A beam of electrons obtained from a heated tungsten filament is accelerated through a high potential. It hits a nickel crystal and the electrons are scattered in different directions. The diffraction pattern obtained is similar to Bragg's experiment on diffraction of X-rays.
It is deduced that electrons too have wave nature as the X& rays have wave character. Only waves undergoes diffraction and pattern doesn't undergoes diffraction. The wavelength of the waves are nearly equal to the de-Broglie wavelength.
Apart from that G.P Thomson performed a experiment to verify the wave nature of the x-rays excepting the fact that the thin foil of Gold plate is used instead of nickel crystal.
Hope this helped you a little!!!
