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I am learning about charge, but there is one thing I don't understand.

enter image description here

In the above picture, I understand that the balloon sticks to the wall because of the attraction between the negative charge on the balloon and the positive charge on the leftmost part of the wall.

My questions are:

$\bullet$ Why doesn't the negative charge on the balloon flow into the wall once the wall and balloon make contact?

$\bullet$ Don't the excess of electrons on the balloon want to equally distribute themselves among the balloon-wall structure?

EDIT:

I found a video and comment sections that explains what's going on. https://www.khanacademy.org/science/physics/electricity-magnetism/charge-electric-force/v/conductors-and-insulators Thank you.

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  • $\begingroup$ Welcome to Physics Stackexchange! Note we are not a typical internet forum (indeed we're not really a forum at all), so (1) we like to keep questions and answers separate (you are welcome to answer your own question, but link-only answers are insufficient), and (2) in any event words like "edit" and such are unnecessary clutter since we have a revision history - just include everything in your post as though you thought of it at the same time. $\endgroup$ – user10851 Sep 23 '15 at 5:48
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∙ Why doesn't the negative charge on the balloon flow into the wall once the wall and balloon make contact?

Both the balloon and the wall are non conducting. It means that the electrons are bound tightly with the atoms/molecules of the material. With rubbing, enough energy is given to the atoms of the hair by the balloon to extract electrons which stick to the balloon surface due to the electric fields of the atoms , by distorting their charge distributions.

∙ Don't the excess of electrons on the balloon want to equally distribute themselves among the balloon-wall structure?

The excess electrons on the balloon due to its non conductive nature will remain locally on the surface in energy levels that become available once the electron charge distorts the atomic charge distributions. They will slowly dissipate acquiring energy from the thermal energy of the balloon. Touching the balloon to the wall will transfer some electrons depending again on energy levels activated by the new charge distributions.

On a single atom single electron level: The electron from an atom in the hair is hit by a virtual photon created by the rubbing, and then is attracted with an exchange of another photon to an empty energy level of an atom, turning it into a negative ion and releasing a real thermal photon. That is why there is heat with rubbing. This extra electron is lightly bound, and thermal energy is enough to supply a virtual photon that will free it.

In conductors dissipation is fast because there exists a collective energy level where the electrons can find an energy level niche that is common to all the conductor.

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  • $\begingroup$ IF the balloon is non-conducting, how did it take electrons from the hair? So electrons can enter a non-conducting material but cannot leave it? $\endgroup$ – Francis Galton Sep 23 '15 at 3:40
  • $\begingroup$ If it were conducting it would not show the effect. They can leave the nonconductive material when a conducting one touches it, ans slowly radiated away picked up by ions in the air when they acquire enough energy from thermal transfers. $\endgroup$ – anna v Sep 23 '15 at 3:54
  • $\begingroup$ on the how: the rubbing supplies energy , the atoms on the surface of the balloon transfer energy through an exchange of a photon to an outer electron in the atoms of the hair , and the electron is caught in an energy level on an atom of the balloon making it into a negative ion. $\endgroup$ – anna v Sep 23 '15 at 3:58

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