Predict and test the behaviour of ฮฑ particles fired at a Rutherford atom model.
(a) Predict the paths taken by ฮฑ particles that are fired at atoms with a Rutherford atom model structure. Explain why you expect the ฮฑ particles to take these paths.
(b) If ฮฑ particles of higher energy than those in (a) are fired at Rutherford atoms, predict how their paths will differ from the lower-energy ฮฑ particle paths. Explain your reasoning.
(c) Predict how the paths taken by the ฮฑ 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?
(d) Now test your predictions from (a), (b), and (c).
Open the Rutherford Scattering simulation (http://openstaxcollege.org/l/16PhetScatter) and select the โRutherford Atomโ tab. Due to the scale of the simulation, it is best to start with a small nucleus, so select โ20โ for both protons and neutrons, โminโ for energy, show traces, and then start firing ฮฑ 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 โmax,โ and start firing ฮฑ 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 โ40โ for both protons and neutrons, โminโ 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 ฮฑ particles? Be clear and specific.
