eli5: static electricity; how does conductor regain neutrality?

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Hi everyone,

Similar questions about static electricity have been asked on here but I couldn’t find one that addresses my exact question, after reading through posts and watching videos, I have a (very) basic idea of how electricity works(kind of). Keep in mind, I’m still very much a novice.

Every material is made of atoms, atoms can be negatively charged, positively charged or have a neutral charge. Atoms are made up of protons, neutrons and electrons, all atoms have the same number of protons to electrons, nature likes balance. There exists conductive materials such as copper,gold and silver. These materials have one loose electron in their outer shell, which they can give up. When a voltage is used, the voltage forces the electrons to flow to the end of the terminal with less electrons to try restore balance. Obviously this only happens in a closed circuit.

With static electricity; when you shuffle your feet on a carpet, the carpet picks up electrons from your feet, since the carpet is an insulator, it doesn’t give up it’s electrons(allow the passage of electrons) but instead a build up of electrons form on the surface of the carpet. Your body is now positively charged as it has more protons than electrons, when you touch a conductor such as a metal door handle, the electrons jump from the conductor to your body to restore a neutral charge in your body.

The question is: if the metal door handle loses/gives up electrons to our body to restore balance, and atoms always seek balance, how does the door handles atoms restore balance from these lost electrons? does it create extra electrons to restore balance from these lost electrons?

Thanks

In: 3

3 Answers

Anonymous 0 Comments

It’s the humidity in the air. Water particles contain enough charged salt ions that are willing to absorb the excess electrons, or are able to provide electrons to
Some extent. It’s a slow process but fact that you get electrically charged much easier in dry air shows that water is playing a big part in equilibrating charges

Anonymous 0 Comments

Air

So you’re not a great conductor so the electrons or lack of electrons are only on your surface. Voltage is based on how concentrated the charges are so bundling them on the surface results in some pretty high voltages

When you touch something conductive it pulls charges from it’s whole mass because they can move easily from inside to outside. Now the difference in charge is very spread out so the voltage is lower. Total excess charge is the same but it’s less concentrated

Over time random air and water molecules bumping into the carpet will pick up charge and ones hitting the door knob will give up a charge to get everything back balanced. Humidity actually plays a big role in this and allows the air to more efficiently conduct the random electrons to their homes which is why you can’t shuffle along the carpet and get a zap on a humid summer day but can easily on a dry winter day

Anonymous 0 Comments

1) “…atoms can be negatively charged, positively charged or have a neutral charge.”

This is incorrect. Atoms have a neutral charge. A positively or negatively charged “atom” is actually an ion, not an atom. Pedantic sure…

2) Electrons don’t flow like water. Electrons flow very slowly and tend to not move very far from their starting point. Electrons do not generally complete the entire electric circuit. They move a little bit, causing the area they left to become positively charged which attracts electrons from down the line. Then a different electron will move along pulling another behind it, and so on.

3) The electrical force is actually a VERY strong force. It is about 1/100th of the Strong force, 10,000 times stronger than the weak force, and about 100,000,000,000,000,000,000,000,000,000,000,000,000,000 times stronger than gravity. It doesn’t take a very large imbalance of electrons to generate a large force.

4) Static electricity requires an insulator. You might say that the insulator traps the electrons once they are dropped off there; however, it is better to say that the insulator slows the electrons’ escape because electrons are not very mobile in an insulator. No matter how good your insulator, it doesn’t have an infinite resistance. Over time the extra electrons are going to leak out taking a variety of different paths. Creating a static charge is just loading up extra electrons faster than they can discharge.