question_answer 61)

                                                                A neutron beam of energy E scatters from atoms on a surface with a spacing d = 0.1 nm. The first maximum of intensity in the reflected beam occurs at  = . What is the kinetic energy E of the beam in ?

Answer:

                  Here,    d = 0.1 nm, , n = 1. According to Bragg's law  or  or