試題詳解

Problem 13:
Here is the Davisson and Germer experiment, illustrating electron diffraction from a Ni crystal.
Which of the following modifications can increase the diffraction angle?

(A) Increase the electron velocity.
(B) Decrease the electron velocity.
(C) Keep the same velocity but replace the electron with an alpha particle (He+).
(D) It is not possible to change the diffraction angle.

(E) Use a crystal with a smaller lattice spacing (more dense periodic structure).