Beta decay and Heisenberg principle

Heimisson
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Homework Statement



One could imagine that beta decay was due to a electron initially inside the nucleus and than leaving it. Proof by using Heisenberg uncertainty principle that this is not possible.

There is a hint which says you can use energy spectra and values for the energy of beta particles.



Homework Equations





The Attempt at a Solution




I think this has something to do with the energy being continuos and that the beta particles can have very different energies but I really have no idea how to proof this.
 
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the electron is too big.

This is the sort of thing that they should just tell you. Its ridiculous for them to expect you to figure it out yourself. There is much better things that you could be spending your time and energy figuring out. Either your book or your teacher or both stinks.
 
granpa said:
the electron is too big.

This is the sort of thing that they should just tell you. Its ridiculous for them to expect you to figure it out yourself. There is much better things that you could be spending your time and energy figuring out. Either your book or your teacher or both stinks.

Thanks for this information

Well my teacher is new and the book isn't very good. Could you explain a little better maybe. This is on a graded assignment. that I have to turn in tomorrow.
 
I'm not allowed to do homework for you.
 
I didn't really ask for that.
 
Ok so I solved this I think.

The only thing I needed to do was find some information on the standard devision of the intensity vs. momentum of beta particles which is gaussian and than use that in the uncertainty principle that showed me that the minimum uncertainty of x is more than two decades larger than the average nucleus. So there is a room for errors in the estimation for the uncertainty of p.

@granpa, thanks for the hint.
 
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