1. Explain why the scattering differential cross section is isotropic if only the 1 = 0 state participates in the interaction that produces the scattering.
2. A very large part of what we know about the forces acting in atoms is obtained from the study of the bound states of the simplest atom, hydrogen. Why is only a small part of what we know about the forces acting in nuclei obtained from the study of the bound states of the simplest nucleus, deuterium?