Static Electricity: Why We Get Shocks on Carpet & Door Knobs

AI Thread Summary
Static electricity occurs when electrons are transferred between materials, leading to a charge imbalance. When rubbing feet on carpet, the human body typically gains a negative charge, contrary to the triboelectric series suggesting it should be positive. This charge transfer results in an electric shock when touching a conductive object like a door knob, as electrons jump to balance the charge. Insulating materials, such as socks, influence this process by either gaining or losing electrons, complicating the charge dynamics. Overall, the movement of electrons is influenced by material properties and the conditions under which they interact.
Biker
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Here is the rub. Most of the online sources and in a kind of statement in my book says that we gain a negative charge when we rub our feet on the carpet. So when we touch a door knob we get a electric shock because the electrons is transferred from us to the door knob

However, Shouldn't it be the opposite? In the triboelectric series, Human body is on the top of the list.. So it is supposed to have a positive charge not a negative one.

Here is the series if you want it : http://soft-matter.seas.harvard.edu/images/8/8e/Tribo.png
 
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Biker said:
Here is the rub. Most of the online sources and in a kind of statement in my book says that we gain a negative charge when we rub our feet on the carpet. So when we touch a door knob we get a electric shock because the electrons is transferred from us to the door knob

However, Shouldn't it be the opposite? In the triboelectric series, Human body is on the top of the list.. So it is supposed to have a positive charge not a negative one.

Here is the series if you want it : http://soft-matter.seas.harvard.edu/images/8/8e/Tribo.png

The positive charge is the proton. The negative charge is the electron. The proton has more mass than the electron, so has a higher inertia (resistance to movement). So it is easier to move an electron (negatively charged) than a proton (positively charged).
 
Kyx said:
The positive charge is the proton. The negative charge is the electron. The proton has more mass than the electron, so has a higher inertia (resistance to movement). So it is easier to move an electron (negatively charged) than a proton (positively charged).
I haven't said anything about moving a proton... I said that the electrons moves from us to the carpet not the opposite. So we will be left with a positive charge.
 
Biker said:
I haven't said anything about moving a proton... I said that the electrons moves from us to the carpet not the opposite. So we will be left with a positive charge.

Insulating materials are more likely to lose or gain electrons, so the socks that you wear are gaining/losing the electrons. By taking your foot off the floor, you are causing the electrons to no longer be able to get back to the carpet, so you are 'spreading' the charge around your body. Then when you touch the door knob, the electrons 'jump'.
 
Biker said:
However, Shouldn't it be the opposite? In the triboelectric series, Human body is on the top of the list.. So it is supposed to have a positive charge not a negative one.
Usually you're rubbing your shoes against the carpet, not your skin. (But interesting question.)
 
Biker said:
So when we touch a door knob we get a electric shock because the electrons is transferred from us to the door knob
The direction doesn't really matter, but if you wear shoes or socks, see Doc Al.
In addition, this triboelectric series is an oversimplification, you often get different regions of different charge, even if you rub two identical materials against each other.

Kyx said:
The positive charge is the proton. The negative charge is the electron. The proton has more mass than the electron, so has a higher inertia (resistance to movement). So it is easier to move an electron (negatively charged) than a proton (positively charged).
It is clear that electrons move, but that doesn't answer the question in which direction the electrons move.
 
Kyx said:
The positive charge is the proton. The negative charge is the electron. The proton has more mass than the electron, so has a higher inertia (resistance to movement). So it is easier to move an electron (negatively charged) than a proton (positively charged).
mfb said:
It is clear that electrons move, but that doesn't answer the question in which direction the electrons move.
Nor is it an accurate description of why it is easier to get the electrons to go between materials. The outer electrons are much more loosely bound to the material than the inner electrons and nucleus. Which direction the electrons go depend on things such as the electronegativity of the materials.
 
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