In an electron-diffraction arrangement using a nickel crystal ( )
PHYSICS · Multi-part · A Level · Physics · Particles and radiation · Particles and radiation
Problem
In an electron-diffraction arrangement using a nickel crystal (d=0.091nm), the second-order intensity maximum is observed at a glancing angle of 65∘.
(i) Calculate the potential difference V1 through which the electrons were accelerated. Take h=6.626×10−34Js, me=9.11×10−31kg and e=1.6×10−19C.
(ii) If the accelerating potential is increased by 200V while keeping all other conditions unchanged, determine the new glancing angle θ2 at which the first-order maximum will now appear.
(iii) Briefly justify whether the angular separation between successive maxima will increase or decrease as the accelerating potential is raised, keeping the crystal the same.