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Your license plate lights won't come on after checking bulbs and changing fuse?
the wirehas been eaten by rates of mouse
Does electricity continue to flow through a table lamp when the switch is on and the bulb is removed from the lamp?
Electricity flows by any conductor.But the most used to flow electricity is copper. Now if there is any problem with a wire even if it is a conductor the electricity will not flow.Sometimes when trying to make an electric circuit the electricity does not flow,if the wirehas no problem it is a problem with connection to make that work you just put silver paperbetween the 2 wires that have a problem in connecting to the bulb or any such thing.
Why does a super-cooled magnet conduct a bigger magnetic field than a normally heated magnet?
That's true about electro-magnets ... the kind that become magnetic when they'reinside a coil of wire carrying an electric current.The greater the electric current is in the wire, the stronger the magnet becomes.So to make a super-strong magnet, you'd want to pass a super-dooper largecurrent through the wire. The problem is that at normal room temperature, wirehas some electrical' resistance. The combination of resistance and current makespower-dissipation. That means heat radiated from the wire, possibly mega-hotif you try to push too much current through it.Now don't get ahead of me here.So far, you might think that "super-cooling" means blowing all that heat away fromthe wire so you can keep pushing big current through it. That's a great idea, butthat's just ordinary cooling, not 'super' cooling.There are some materials which, when they become 'super cold' ... like only a fewdegrees above absolute zero, become "super-conducting" ... they lose all of theirelectrical resistance. Not that it becomes very low ... it becomes totally zero! Theheat produced by enormous current flowing through a wire made of that materialis zero.And the coolest part is: Once they start an enormous current flowing through thatcoil of wire, they can actually connect the ends of the coil together, take the powersupply away, and as long as the coil stays super-cooled, the current keeps goingaround and around and never decreases, for months, because the wire in the coilhas zero resistance. Is that mind-blowing or what!So a normal magnet, connected to a normal power supply with high current, canproduce a strong magnetic field. A "super-conducting" magnet, with a giganticcurrent flowing through it and no power supply, produces an enormous magneticfield, as long as it's kept super-cooled.So strong that it'll pull paper-clips out of your pocket when you walk into the laboratory.(I met my wife in an MRI research lab where there was a super-cooled magnet.)
