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Q & A: 92 protons in one nucleus?

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Most recent answer: 09/13/2012
Q:
I once read on a website that protons move on their axis is that true? And secondly protons have the same charge then how such large number like 92 can easily stay in the nucleus. Why do not they repel each other? Please answer in simple words.Thank you
- Areeba (age 16)
Islamabad,Pakistan
A:
There are two forces that act on protons.  One is the Coulomb force which for two or more protons is repulsive and tends to make them fly apart.  The second is the nuclear or strong force that has a very strong short range attractive force.  Protons are also attracted to their neutral counterparts, neutrons, via the strong force.  These two forces compete with each other in various combinations of neutrons and protons in nuclei.   If there are too many protons the nucleus will be unstable and decay due to Coulomb repulsion.  A nucleus with too many neutrons is also unstable but for a different reason.   A neutron is a bit heavier than a proton and the weak interaction will allow a single neutron to decay into a proton plus an electron and an  anti-neutrino. 
Nuclei with the same number of protons but different number of neutrons exist.  They are called isotopes.  Some are stable, others not and will decay by alpha or beta emission.

I don't understand your first question.

LeeH

(published on 09/13/2012)

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