: if you disconnect a power cable, where does the electricity that is still in the cable go?
In: 40
The charge or electrons move when a circuit is complete. Disconnect the cable and the electrons stay where they were. Like marbles in a tube. One pushed in and they push each other out. Like electrons. Stop putting marbles in. The marbles stay.
It doesn’t “go” anywhere. It ceases to be. Electricity isn’t a “thing” it is what we call it when electrons are moving in a particular way. When you unplug a cable, the electrons stop moving in that particular way, so there is no more electricity.
Hum. Now stop humming. The hum has not gone anywhere. It simply ceased. Energy is not a thing. It’s a process.
Maybe this analogy may help. Think of electricity like a string running through two straws. Pulling the string back and fourth quickly is the “electricity”. If you cut the string in the middle (unplug the outlet), the strings stop moving.
there are plenty of ELI5s that discuss the basics of electrical flow and how a formed circuit is required to conduct electricity through a device, so by unplugging it you are breaking the circuit between the common and hot prongs and removing the path for electricity to flow- but I’m guessing this isn’t what you are really asking…
assuming you are asking about the energy that was traveling through the cable at the time it was disconnected, it pretty much stays there as static charge (capacitance) as long as nothing is draining it from the other side, with the amount of charge left based on the cable properties (thickness, conductance, etc) and the voltage that was driving the current flow. things that could drain the static charge on the other end include transformers, power regulators, or based on the way the source unit is grounded. in heavy power transmission lines, this is typically called “residual power” and can be very dangerous, though it has more to do with the actual capacitors involved and less-so the capacitance of the cables.
I’ll use the water analogy.
When you open your tap, water flows. When you close it, it stops.
Now you might be thinking that electricity is the WATER in this analogy. That is false. electricity is the FLOW of water.
No flow, no electricity.
Electricity flows from *Potential*, essentially if you unplug a cord which was not powering anything, nothing happens, which is why you never see a spark when you plug in or unplug an extension cord which is not plugged into a device at the other end. So in this case, there actually was no electricity in the cord, since it had nowhere to go.
If you plug in or unplug a cord with a high draw device running, such as an Iron or an air conditioner, you will likely see or hear (or both?!?!) a spark, because in this case there is electricity flowing, not just potential. In the case of unplugging the device which is drawing the current, the remaining electricity is used up by the device, often instantly. However in some cases such as LED bulbs, they will remain lit for some time after the current is disconnected as they can make a little bit of electricity go a long way.
The same place that traffic flow goes on a busy road when the lights go red, basically. The road is still full of vehicles; they’re just not going anywhere. Electricity is much the same.
Think of cars moving on a road. When you unplug the cable its like you turn the light red and the cars stop.
The grid is basically a machine that balances generation of electricity with consumption in real time.
Any time a load is added or subtracted, a corresponding amount of generation must occur. There is a little wiggle room, but not much.
So if a large power cable is cut, the grid either has to find an alternative destination for the supply, or it needs to cut supply by that amount.
If the question is where the physical electricity in the wire goes, the best answer is that there is no electricity in the wire to go anywhere. The confusion likely comes from our shorthand thinking about electricity in that we think of it like water in a pipe. It’s not really. That’s a useful analogy that’s not confusing for people, but it falls apart when too many questions get asked… Because it’s not really the way things work. Think of a wire more like a phone line that tells a device in a circuit to consume power. So when the wire is cut, the flow of information stops rather than a bunch of electrons spill out on the ground.
This is still not completely accurate. Unfortunately there’s no EILI5 for how electricity actually works. Which is why people just pretend it’s angry pixies in a pipe. It’s close enough that the average Joe off the street can wire an outlet.
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