this post was submitted on 31 Oct 2023
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Nah, two atoms repelling is not relative. They will do that in every reference frame.
For sure but we have no absolute charge measurements, really for all we know were super positively charged, but so are all our voltometers so everything balances out
No, because we'd be flying apart, or at least our hair would stand up. Negative vs positive are relative, but distance from neutral is not.
Charge and voltage are slightly different, maybe that's where you're caught.
To highlight this we gotta disect your answer a little.
Why does your hair stand up when charged? Because the relationship between each other is similarly charged, and the air less similarly - so its going to have the force of gravity, and those 2 charges affecting it.
If you increase both charges from our 'neutral' by one yes your hair repels itself greater, but so does the air around it.
Similarly if you were on a super charged planet/atmosphere, your hair wouldn't stand up at all cause the atmosphere is charged and you are grounded to it - but the second you change your relative environment to earth you'd probably pass out from the discharge
Stuff stands on end in a vacuum too, though. I don't know about the effect of the presence of air exactly, but the basic phenomenon doesn't depend on it. In electrical engineering where you mostly care about voltage it's convenient to pick a relative ground, but in physics Coulomb's law is pretty unambiguous:
|F| = k~e~*q~1~*q~2~/r^2^
Where q are the charges in question, measured in Coulombs, r is distance and k~e~ is a fundamental constant. For contrast voltage is energy per distance per Coulomb. If we were to add a constant charge to both sides:
|F|=k~e~(q~1~+1)(q~2~+1)/r^2^
|F|r^2^/k~e~=(q~1~+1)(q~2~+1)
|F|r^2^/k~e~=q~1~q~2~+q~1~+q~2~+1
You'll notice that even if we assume no charge was present in the first place, the +1 means that now the two objects will repel. Doing the same thing subtracting from one of them, assuming they're both the same, produces a difference of squares and will decrease repulsion or add attraction, again without requiring any charge in the first place.
The Earth probably does gain a very slight electric charge as it interacts with the solar wind, but it's tiny and I'm not sure if it has ever been measured.