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Q & A: alpha particle scattering

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Most recent answer: 10/22/2007
Q:
Alpha particles are fired at a very thin gold layer is the experiment in disscusion.
What would happen if an alpha particle hits head up an electron and this electron is in a straight line with the nucleus. After this electron hits the nucleus what would happen to the atom.(A very rare event of course.)
(Geiger and Marsden`s scattering experiments.)

Thanks for reading my question. Please make an announcment if the question can not be answered.
(I also asked the question linking terminal velocity,air resistance and Newton law`s of motion.)
Ps:My physics teacher could not answer the question so please help me get my ideas in order.
- Ylli Bole Kopani (age 17)
Vlora
A:
You are thinking in terms of classical mechanics where electrons and alpha particles are like hard billiard balls and bounce around according to what you would expect on a pool table.
In the real world of atoms and atomic collisions, quantum mechanics changes the rules of the game such that the classical trajectories are no longer followed strictly.  Of course the laws of conservation of energy and momentum still have to be obeyed in the quantum case. 

So the question can be answered but only in terms of angular probibility distributions that can be calculated using quantum mechanics.  By the way, there is a finite probability that the electron can emerge on the opposite side of the atomic nucleus as if it passed through it.

Lee H

(published on 10/22/2007)

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