Chapter 28: Problem 10
Neutron diffraction by a crystal can be used to make a velocity selector for neutrons. Suppose the spacing between the relevant planes in the crystal is \(d=0.20 \mathrm{nm}\) A beam of neutrons is incident at an angle \(\theta=10.0^{\circ}\) with respect to the planes. The incident neutrons have speeds ranging from 0 to \(2.0 \times 10^{4} \quad \mathrm{m} / \mathrm{s} .\) (a) What wavelength(s) are strongly reflected from these planes? [Hint: Bragg's law, Eq. \((25-15),\) applies to neutron diffraction as well as to x-ray diffraction.] (b) For each of the wavelength(s), at what angle with respect to the incident beam do those neutrons emerge from the crystal?
Short Answer
Expert verified
2. What are the given values for d and θ in this exercise?
3. Which steps should be followed to solve this exercise?
4. What is the angle of emergence for the calculated wavelength(s)?