Question:
A proton has spin and magnetic moment just like an electron. Why then its effect is neglected in magnetism of materials?
Solution:
The comparison between the spinning of a proton and an electron is done by comparing their magnetic dipole moment which is given as
μp = eh/4πmp
μe = eh/4πme
μp/μe = me/mp = 1/1837 >> 1
μp << μe