Give an example of what we can learn about matter through the use of momentum and energy conservation applied to scattering experiments. Explain what it is that we cannot learn this way, for which we need to measure the distribution of scattering angles.

The momentum and energy conservation applied to scattering experiments.

The law of conservation of momentum asserts that if a system of bodies has no net external forces acting on it, the total momentum remains constant at all times (it is conserved). If all forces, external or internal, can be given a potential, then the total energy remains constant as well.

Scattering tests can be used to identify subatomic particles and disclose the structure and behavior of atoms, nuclei, and other tiny particles in matter. (For example, Rutherford identified the nucleus by measuring alpha particle scattering against a very thin gold foil, using the momentum conservation principle).

Scattering angle distributions provide a broader view of the situation (for example, the relative sizes, the incident flux and angular size)