So as we know for a person to get electrocuted a circuit needs to be completed. You cannot stand on a wooden chair and get electrocuted. So when you stand on a wooden chair and touch a live wire, how does the electricity figure out that you’re standing on an insulator? Does the electricity pass through you first before failing to complete the circuit because of the wood?
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Electricity doesn’t “know” or “think” about anything. It behaves according to Physics.
Think about water in a glass. How does it “know” to take the shape of the glass? It doesn’t. It’s just this pile of water atoms that’s being pulled towards Earth by gravity, but the glass is in its way, so the atoms arrange themselves in a pile such that every atom has moved as much as it can and that happens to make the water fill the glass’s shape. It’s not that much different from if you put a lot of sand in the glass.
Electricity flowing down a wire is like water flowing through a pipe. Think of an insulator as a really skinny pipe, like a drinking straw skinny. Think of a conductor as a really big pipe, like a sewer big. If a lot of water is flowing down the sewer and there’s a tiny, straw-sized pipe off to the side, *some* water is going to go down that tiny pipe but not an awful lot because you just can’t fit “big pipe” water into “small pipe” space.
Or, put another way. Suppose I have a big water tank and water’s coming through a fire hose. At the end of the hose, I put a T joint, with one direction funneling into a tiny pipe and another direction funneling into a big pipe. If we measure what’s coming out of both pipes, it’ll be the same amount of water that is in the hose, but far less water will come from the small pipe than the big pipe because less water “fits”.
That’s how electricity moves. Instead of gravity, electricity moves in the direction of “potential difference” which means it tries to get from a place where there’s a high voltage to a place where there’s a low voltage. Think of voltage differences as sort of like a magnet: they suck electricity from where it is to where it isn’t. But also think of it like gravity affects water: if the “pipe” the electricity is flowing through is small (a conductor) it’ll flow VERY slowly.
So let’s say somehow we’ve charged an orb with 10,000 volts. The electricity just sits there, because air is a pretty decent insulator and there just isn’t enough energy in that electricity to push through the teeny tiny pipe that air represents. This is like a bunch of water sitting in a glass. It feels gravity and wants to go to the ground, but there’s just no good path.
Your body is a half-decent conductor. But if you’re floating in zero gravity and you poke the orb, since your body isn’t touching anything at a different voltage not much happens. You might absorb some of the charge, but since the electricity isn’t flowing *through* you we can sort of see it as like you’re “wet” with electricity. It STILL wants to get to the ground but there’s just no path, and it’s the movement of electricity that can cause damage to your tissue.
Now let’s say you barefoot touch the ground. The Earth doesn’t really have a significant charge compared to that 10,000 volts, so it’s going to push itself through your body into the Earth and you’re likely to get hurt from all that energy flowing through you.
But what if instead you barefoot stand on a thick rubber mat? That’s a strong insulator, so there’s still no easy path to the ground. If we do some serious math we’ll notice some tiny amount of electricity will trickle through, but it’s so negligible you won’t feel it and it’ll take ages to see a measurable difference.
So it’s not about electricity “knowing”. It’s about whether the path to the ground it has is a thicc pipe or a smol pipe. Also notable: if the voltage gets high enough, it CAN arc through air and could even push its way through a rubber mat. Imagine trying to funnel all of the water behind the Hoover Dam through a drinking straw. It’d destroy the straw because there’s just so much pressure.
(This is all a little hand-wavy to keep it simple, there’s also the concept of “current” I could’ve discussed. But in general, if voltage is really big current is going to be bigger, and if the “pipe” is “bigger” then current can be bigger, so adding it in makes things more complex for no good reason.)
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