If a wire carrying current produces magnetic field around it, why its not attracted to nearby metals ? In a general household.
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In a straight wire, their magnetism is weak. If you curl it up into a coil, this magnifies the magnetic field, and such a device is called an “air core solenoid”.
If you then insert a iron/steel bar into the center of the coil, it becomes an iron-core solenoid. It can also be called an electromagnet, because the magnetism goes from strong to weak and back to strong as the current is turned on or shut off.
It is. That is one ot he reasons there is a thick protective skin of plastic around the wire.
If you are an electrician, then you know “Left Hand rule”. Make a fist with your left hand and extend your thumb. If current is flowing in the direction your thumb is pointed, an electromagnetic field is generated in the direction your fingers are pointed. This electromagnetic force creates resistance to the current flow. AC switches “Direction” (60 times per second is most common in the US) which continuously reverses the magnetic field, thus preventing resistance from building up,
One more note, that I haven’t seen pointed out here. Even if it was strong enough to be felt, things wouldn’t be attracted towards the wire. Electricity sets up a magnetic field in a circle around the direction of flow. So if the effect was strong enough to be felt you wouldn’t feel things attracted to the walls, you’d feel them try to pull along the wall with the effect getting stronger the closer you are to the wire.
When you coil wire you get an attraction towards the coil because of the coil shape and the looping. It creates a magnetic field that kind of looks like a doughnut looping things toward the center of the coil, making that an attraction point (assuming polarity matches blah blah blah).
While studying low voltage industrial installation, a professor told us elektrical shorts on the main lines could blow cables from their carriers/ walls pure by magnetism
It is attracted, just very weakly.
An analogy for this might be if you had asked “If feathers supposedly weigh something, why didnt I notice there was one in the box of books I was moving?” The error in that question is probably obvious. Of course a feather weighs *something* it’s just incredibly light and not noticeable by a person among other things.
The magnetic fields around household wiring are similarly weak as a feather is light. It’s attractive to metals, but so little you’d never notice. You could put that feather on a scale or hold an EMF detector next to a wire and in both cases you’ll get a clear reading. It’s just not strong enough to feel with your hands or whatever.
It is. It’s a weak effect, but with a very light wire and a lot of current you can see it twitch.
Its not ELI5 but if you want to know more than 99,999999% of the world about that topic – watch the Veritaserum video. Its sooooo good.
TLDR: We simplified “electrons moving trough a wire” too much. Everyting imagines it wrong, even proffesionals.
It does, the magnetic field is just weak and decays quickly with distance. But it is what wire finders use. There is another case where this becomes important. If you have a long extension cord that is stored on a reel, then the magnetic field can induce a counter current in the loops on the reel, causing losses and making the cable heat up. That’s why cable reels usually have different max powers given on the label.
As others have said, there is a weak magnetic field, but what I haven’t seen mentioned yet is that only a certain small set of metals are influenced by a magnetic field. In a household that will be ferromagnetic metals like iron (not stainless steel) and nickel, which don’t tend to be that common in modern houses (if you ignore nails, beams and some furniture). That said, without significant coiling, the effect is going to be almost negligible unless, perhaps, the cables are dangling right next to an iron beam.
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