What is true nucleus and electron?

Why neutrons have high mass than positively charged protons?
Why electrons are considered as nearly mass less, but how this masses electron makes the atom electrically neutral? How this nucleus causes mass?

Why we call protons as positively charged particle and why we call electron as negatively charged particle?
Why electron spin nucleus, what is the true mechanism and forces which control the electrons orbit?

Ok, what is the source of this atomic magnetic force in atom?

By true law of atom,  now we know that all atoms has a very powerful atomic magnetic force, then nucleus and electrons are the source of this atomic magnetic force, so nucleus and electrons also have powerful magnetic field in them. The magnetic field in nucleus was the main reason or source for cause of mass in atom.

So, powerful atomic magnetic force was created by the source of nucleus and electrons in the atom.

Let us call the nucleus magnetic field as positively charged atomic magnetic force (+amf) and let us call electron magnetic field as negatively charged atomic magnetic force (-amf).

Even electron has powerful magnetic field, but why they have nearly very less mass?
Yes, nucleus and electrons also have powerful magnetic field in them, but magnetic polarities of each of them are opposite to each other and work like a coupled.
When we compare to earth magnetic field electrons have unlike amf.

Simply, mass is an attraction force in between two like atomic magnetic force, so mass is a resultant force of two like’s amfs or two fundamental forces.

I think you are now able to understand the true reason for nucleus causes mass in atom. Now let us see some more deep in nucleus. Why neutrons have high mass than protons because neutrons have high positively charged atomic magnetic force (+amf) than protons.