Name: Greg H.
Why do neutrons stay in the nucleus of an atom? We
just covered that in our science class and I was wondering since they
have a negligible charge and I cannot see why they are there. If neutrons
can go in a nucleus like that, what is there to stop them from forming a
complete atom of their own? made just from neutrons?
It is believed that the nucleus of an atom is not held together by electric
force. In fact, it must be a force much stronger than the electric force.
If it were not, the protons in a nucleus would push each other away. This
force has been labelled the Strong Force. Protons, neutrons, and other
particles made of quarks feel this force. It is always attractive. The
best-working model for it has protons and neutrons interacting with each
other through the exchange of particles, usually particles called pions.
This very strong, attractive force holds protons and neutrons just as well.
It has nothing to do with electric charge.
Electrons do not feel the Strong Force. The strongest force electrons
respond to the electric force. This is why a neutron cannot hold an
electron in orbit. A neutron, having no electric charge, does not use the
I expect you to wonder why these things are so. Nobody knows why they have
to be. We have theories about how these forces work, and about what allows
particles to feel them. Science can explore how the universe works, but
science cannot discover why the universe is designed as it is.
Dr. Ken Mellendorf
Illinois Central College
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Update: June 2012