Some additional questions I have to further understanding:
Ships don’t have ground, but why couldn’t electricity on a ship ground to the ocean the same way houses ground to the earth?
A structure will have a grounding rod dug into the earth. Does the dirt, soil, and rock composition that the structure is built on affect how willing current is to use the path?
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Another point that some of the top comments seem to be missing is that there is also a ground terminal at the transformer where you get the power. If you’ve taken a basic circuits course you know that current needs to move in a, well.. Circuit. Most transformers that supply the power you use at home or at work are grounded transformers, meaning they have a huge conductive rod sticking in the ground that “sucks up” any current passing through a ground fault and returns it to the circuit.
Another point that some of the top comments seem to be missing is that there is also a ground terminal at the transformer where you get the power. If you’ve taken a basic circuits course you know that current needs to move in a, well.. Circuit. Most transformers that supply the power you use at home or at work are grounded transformers, meaning they have a huge conductive rod sticking in the ground that “sucks up” any current passing through a ground fault and returns it to the circuit.
On a vehicle, the return path is generally the metal structure of the vehicle, sometime referred to as ground (but has nothing to do with real ground, or water for the matter). This allows to run a power line to an item and let the current go back to the generator through the vehicle chassis instead of using additional wires. But in some case is still preferable to use wired return path instead, especially for high power applications or on vehicles that are not mainly metal-made.
On land, you have the power wire and the return wire, altho in AC they are named differently, still that power flows to the user form a wire and back to the powerplant in another wire. Because as you say, ground is not a reliable conductor. In this case the word ground is used for an actual wire to the ground. But this ground line is used to dissipate whatever charge escapes the normal system. This provides a backup path for these “leaks” and usually is enough to prevent accidental electrocution of people, and prevent/mitigate electric fires, in case of faulty or damaged circuits.
I think the OP is also asking WHY does electricity want to go to the earth. Electricity is typically up in the air on hydro poles or along wires buried in a conduit but given the opportunity, electricity wants to go to ground/earth.
I think the OP is also asking WHY does electricity want to go to the earth. Electricity is typically up in the air on hydro poles or along wires buried in a conduit but given the opportunity, electricity wants to go to ground/earth.
On a vehicle, the return path is generally the metal structure of the vehicle, sometime referred to as ground (but has nothing to do with real ground, or water for the matter). This allows to run a power line to an item and let the current go back to the generator through the vehicle chassis instead of using additional wires. But in some case is still preferable to use wired return path instead, especially for high power applications or on vehicles that are not mainly metal-made.
On land, you have the power wire and the return wire, altho in AC they are named differently, still that power flows to the user form a wire and back to the powerplant in another wire. Because as you say, ground is not a reliable conductor. In this case the word ground is used for an actual wire to the ground. But this ground line is used to dissipate whatever charge escapes the normal system. This provides a backup path for these “leaks” and usually is enough to prevent accidental electrocution of people, and prevent/mitigate electric fires, in case of faulty or damaged circuits.
“Ground” is just a huge volume of mass that is in electrical equilibrium with itself everywhere. Basically, like how water flows downhill until it finds an ocean (the place where all the other molecules have the same energy from gravity), excited electrons keep passing on their excitement until they find a place where they lose it to the crowd. They used to be “Uphill” and now they are down here at sea level with everything else.
electrical ground is just sea level for gravity. Everything shares the energy equally.
“Ground” is just a huge volume of mass that is in electrical equilibrium with itself everywhere. Basically, like how water flows downhill until it finds an ocean (the place where all the other molecules have the same energy from gravity), excited electrons keep passing on their excitement until they find a place where they lose it to the crowd. They used to be “Uphill” and now they are down here at sea level with everything else.
electrical ground is just sea level for gravity. Everything shares the energy equally.
If we had a thin wire of earth it would be a very poor conductor. But we don’t, we have a big old lump of earth and the current can spread out wide and far to really low current densities and absorb ridiculous amounts of electricity (where does the lightning go?).
The weak link is the connection with the ground and that’s why they bury the ground into earth, for serious grounding applications this can involve quite a bit effort to ensure a good connection with the earth. And not having a good earth connection can and does cause problems.
If we had a thin wire of earth it would be a very poor conductor. But we don’t, we have a big old lump of earth and the current can spread out wide and far to really low current densities and absorb ridiculous amounts of electricity (where does the lightning go?).
The weak link is the connection with the ground and that’s why they bury the ground into earth, for serious grounding applications this can involve quite a bit effort to ensure a good connection with the earth. And not having a good earth connection can and does cause problems.
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