what exactly is isospin?
have you tried google it? What do you already know about it?
all i know is that it is nuclear spin and that it is a conserved quantity like angular momentum
Why don't you start here?
well hmm nuclear spin. It is a symmetry concept, that the proton and the neutron are treated similar with respect to the strong force, so they both have magnitude of isospin: ½. And the proton is regarded as the iso-spin up particle of the nucleon, and neutron as the spin down of the nucleon.
But there is a lot out there on the internet, search and read and perhaps come back here if you have a specific question =)
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