Rutherford Backscattering Experiment

AI Thread Summary
Rutherford's backscattering experiment successfully demonstrated the existence of the atomic nucleus by using a thin gold foil and bombarding it with alpha particles, which are much lighter than the target nuclei. The scattering formula derived by Rutherford assumed point charges, which worked well due to the significant mass difference between the alpha particles and gold nuclei. Deviations from this formula occur when the target foil is thicker or when the masses of the incident particles and target nuclei are comparable, leading to more complex ion-solid interactions. The experiment's historic significance lies in confirming that most of an atom's mass is concentrated in the nucleus, rather than being evenly distributed. This foundational discovery reshaped the understanding of atomic structure.
TauDay
Messages
5
Reaction score
0

Homework Statement



In the famous “Rutherford backscattering” experiment, alpha particles (Z=2) of
approximately 7 MeV were used to bombard a Au (Z=79) film. Rutherford derived the
scattering formula by treating an incident alpha particle and a Au target atom as two point
charges with their charge numbers equal to their atomic numbers. This assumption, however,
is not accurate in describing general ion solid interactions. Explain
(a) why was Rutherford’s approach successful in his experiments?
and
(b) under what conditions deviation from Rutherford scattering formula will occur?



Homework Equations





The Attempt at a Solution



a) Rutherford’s approach was successful because he used an extremely thin foil with a target nucleus much heavier than the incident alpha particles.

b) If the foil was thicker and the target nucleus and incident alpha particle were of comparable mass, Rutherford would have observed increased ion-solid reaction types.
 
Physics news on Phys.org
The thin foil is certainly an important point. The heavy nucleus is something the scattering formula can take into account.

I think the question asks for something that you missed so far. What was the important historic result of the experiment? If you know the result in advance (as we do know) it might look obvious, but at that time it was unclear.
Hint:
What about electrons, for example?
 
The result was confirmation of the atomic nucleus - most of the foil's mass is concentrated and not evenly distributed.
 
Thread 'Help with Time-Independent Perturbation Theory "Good" States Proof'
(Disclaimer: this is not a HW question. I am self-studying, and this felt like the type of question I've seen in this forum. If there is somewhere better for me to share this doubt, please let me know and I'll transfer it right away.) I am currently reviewing Chapter 7 of Introduction to QM by Griffiths. I have been stuck for an hour or so trying to understand the last paragraph of this proof (pls check the attached file). It claims that we can express Ψ_{γ}(0) as a linear combination of...
Back
Top