State what is meant by the de Broglie wavelength.
An electron is accelerated from rest in a vacuum through a potential difference of 
.
Calculate the de Broglie wavelength of the accelerated electron.
By reference to your answer in (i), suggest why such electrons may assist with an understanding of crystal structure.
is the de Broglie wavelength, 
is Planck's constant and 
is the momentum of the particle.
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