A Crystal Diffracts a Beam of Electrons, Like a Diffraction $0.18 \mathrm {~nm}$

Short Answer

A crystal diffracts a beam of electrons, like a diffraction grating, as they hit it perpendicular to its surface. The crystal spacing is $0.18 \mathrm {~nm}$ , and the first maximum scattering occurs at $80 ^ { \circ }$ relative to the normal to the surface. $\left( e = 1.60 \times 10 ^ { - 19 } \mathrm { C } , m _ { \mathrm { e } } \right.$ ectron $\left. = 9.11 \times 10 ^ { - 13 } \mathrm {~kg} , h = 6.626 \times 10 ^ { - 34 } \mathrm {~J} \cdot \mathrm { s } \right)$
(a) What is the wavelength of the electrons?
(b) What potential difference accelerated the electrons if they started from rest?