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Consider an electrically neutral object:
Is it going to attract a positively charged object or the negatively charged object?
What is the type of attraction?
How does it attract or why does not it?
Why the positive protons of the atom attracts to the neutral neutrons and the negative electrons does not?
Let's assume that we're talking about macroscopic objects, say particles of soot. The neutral object (call it 'O') will attract either a positively charged object ('P') or a negatively charged object ('N'). Here's why…
If P is placed near O, P will tend to pull the electrons in O towards the side of O nearest P. If O is a conductor, free electrons will move through O; if O is an insulator they will be pulled minute distances within each molecule while the nuclei are pushed minute distances away from P. The result in either case is that O will behave as a dipole with its negative charge closer to P than its positive charge. But P's electric field is stronger the closer we are to P. So P will pull the negative charge of the dipole more strongly than it repels the positive charge of the dipole. So O will experience a net attractive force towards P. And, of course, (appealing to Newton's third law) P will have a net attractive force towards O.
If you go through exactly the same argument, but with N instead of P placed near O, and remembering that N's electric field will be in the opposite direction to P's, (that is N repels electrons and attracts nuclei) you'll find that N, just like P, attracts O, so O attracts N.
Lets look at 2 cases:
i) When the neutral body is a conductor:
If a charged body is brought near a neutral body, the same charge in the neutral body would get repelled and go to the far side hence accumulating the opposite charge in the near side. By coulombs inverse square law the attraction force on the nearer side overweighs the force of repulsion from the farther side . Therefore a neutral body Is attracted by a charged body.
2)When the body is a dielectric:
Since in dielectrics the electrons are bound to the atom, the atoms get polarized in the influence of electric field created by the charged body. Therefore in the same way As case 1 it gets attracted to the charged body.
Well, ofcourse the attraction is because of electrostatic forces of attraction.
Coming to the next part of the question; the neutron and proton are point charges so there is no question of charges getting polarized so there is negligible force of Electrostatic attraction. Since the protons and neutrons are in the nucleus, nuclear forces operate (at very close distance nuclear forces are immensely strong). The electrons being in the orbits around the nucleus, the nuclear forces are very weak.
Let's suppose we are talking about electric charge. A neutral charged object has not charge at all, provided we are assuming the object as a whole (point particle for example). Thus a neutral object will not interact with a charged one. If you are talking about protons and neutrons in nuclei, the force that keeps them together is not of electromagnetic nature and it doesn't affect electrons.
