Chapter 2, Problem 9E

Predict and test the behavior of a particles fired at a Rutherford atom model.

1. Predict the paths taken by a particles that are fired at atoms with a Rutherford atom model structure. Explain why you expect the $\alpha$ particles to take these paths.

If a particles of higher energy than those in (a) are fired at Rutherford atoms, predict how their paths will differ from the lower-energy a particle paths. Explain your reasoning.

Predict how the paths taken by the $\alpha$ particles will differ if they are fired at Rutherford atoms of elements other than gold. What factor do you expect to cause this difference in paths, and why?

Now test your predictions from (a), (b), and (c). Open the Rutherford Scattering simulation

(http://openstaxcollege.org/I/16PhetScatter) and select the “Rutherford Atom” tab. Due to the scale of the simulation, it is best to start with a small nucleus, so select “20” for both protons and neutrons, “mm” for energy, show traces, and then start firing a particles. Does this match your prediction from (a)? If not, explain why the actual path would be that shown in the simulation. Pause or reset, set energy to “max,” and start firing a particles. Does this match your prediction from (b)? If not, explain the effect of increased energy on the actual path as shown in the simulation. Pause or reset, select “40” for both protons and neutrons, “mm” for energy, show traces, and fire away. Does this match your prediction from (c)? If not, explain why the actual path would be that shown in the simulation. Repeat this with larger numbers of protons and neutrons. What generalization can you make regarding the type of atom and effect on the path of a particles? Be clear and specific.