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[deleted] t1_jefo6np wrote
[deleted]
GalFisk t1_jefolbh wrote
DC is actually better at arcing, because the electric field is constantly on instead of disappearing several times per second. This is the reason you find switches and relays rated for far lower DC than AC voltages.
mmmmmmBacon12345 t1_jefscax wrote
>Is this because we are using AC rather than DC, which creates far more and continuous emr and is capable of much greater induction?
You've misunderstood something somewhere along the way. You're throwing out words in ways that don't make sense
First, why are you discussing Electromagnetic radiation(assuming that's what EMR is since its uncommon to discuss) instead of electric field strength?
DC creates a static magnetic field and a static electric field. The strength of the magnetic field is proportional to the current and the strength of the electric field is proportional to the voltage
AC creates a changing magnetic and electric field but the strength of the magnetic field is still proportional to the current and the strength of the electric field is still proportional to the voltage
Inductance refers to how much energy is stored in the magnetic field and is a property of the windings and magnetic core, not the electricity being fed to it
Since the electric field is proportional to the voltage then the AC and DC ones will have the same average field. The AC will start a breakover a bit sooner due to the higher peak voltage, but if it breaks over the DC line won't stop arcing because the voltage never drops to zero. Its actually a lot harder to get DC to stop ionizing the air.
Chromotron t1_jefqxb3 wrote
> Is this because we are using AC
In addition to the other answer: the strongest example you will likely every see is DC: lightning.
mmmmmmBacon12345 t1_jefrog3 wrote
You compromise the spacing
High voltage wires are relying on the fact that air isn't that conductive and takes a lot of voltage to breakdown and let a lightning bolt pass
If you get too close to them then instead of the electricity needing to jump through air all the way to the ground it only needs to jump through to air to you then pass through your far more conductive body and make the final hop to ground.
Air will block about 3,000,000 volts per meter of air. We don't run it close to that limit but you might find a 300 kV line with a meter of clearance, but if you get less than 10 centimeters from the wire you're now close enough that it can blow through the air and hop to you just like lightning hopping from the cloud to the ground.
Normally voltages you encounter are low enough that it can't arc more than a millimeter, but transmission lines can get up to hundreds of thousands of volts which is enough for some sizable arcs
TheDeadMurder t1_jeg26cx wrote
Contrary to popular belief, electricity doesn't work like how most people believe it does, such as electrons don't move through the wire and circuits don't need to be connected to work, the reason this is taught is because that's the simplest way to explain it
What happens is that electrons are accelerated and dump their energy into protons, then accelerated again by the magnetic field that forms when a power source and load are in a circuit, if you have an electric toothbrushes, wireless chargers
than that's how they work without happening to having to be plugged into by a cable, that's also how transformers covert a high voltage to a lower voltage since the gap between them the two circuits are insulted by enough air to reduce the voltage enough
In most cases, the air is a good enough insulator that this isn't an issue, but once you get to a high enough voltage you do like with your example of high voltage lines or Tesla coils
Emyrssentry t1_jefkwkh wrote
High voltage lines have the ability to ionize the air around them, and turn the air into a wire. If that area of ionized air can reach something that grounds the wire, you'll get an arc. This is lightning.
And so if you get too close, the wire could ionize the air around them, and that ionized air touches you, and since you can ground the wire, it arcs to you, causing electricity to flow through you, potentially stopping your heart.