I understand the concept of DC, but if electrons are just kind of moving back and forth in one place to produce an electric charge for AC, why do they say it’s necessary to have a path back to ground/ 0V if it’s not “moving” towards ground/ 0V?
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>I understand the concept of DC, but if electrons are just kind of moving back and forth in one place to produce an electric charge for AC, why do they say it’s necessary to have a path back to ground/ 0V if it’s not “moving” towards ground/ 0V?
Because if *everything* moves, nothing moves. Also, it **is** moving towards ground. But only for a very short time, followed by moving away from it instead.
>I understand the concept of DC, but if electrons are just kind of moving back and forth in one place to produce an electric charge for AC, why do they say it’s necessary to have a path back to ground/ 0V if it’s not “moving” towards ground/ 0V?
Because if *everything* moves, nothing moves. Also, it **is** moving towards ground. But only for a very short time, followed by moving away from it instead.
You don’t need a path towards ground necessarily, you just need the two ends to be at different voltages. It’s just easier to alternate the voltage on one end and keep the other end constant than to alternate both ends.
You don’t need a path towards ground necessarily, you just need the two ends to be at different voltages. It’s just easier to alternate the voltage on one end and keep the other end constant than to alternate both ends.
AC doesn’t need a neutral. If you’re using neutral and negative interchangeably, then yes it needs a neutral path.
Technically, electricity doesn’t move by electrons but by electromagnetic waves. They’re just really linked together. It’s a common misconception that they move by electrons. Just think about transformers (two coils separated by a gap), there is a gap there but AC can travel across that gap.
You need a complete path for the electricity to travel.
AC doesn’t need a neutral. If you’re using neutral and negative interchangeably, then yes it needs a neutral path.
Technically, electricity doesn’t move by electrons but by electromagnetic waves. They’re just really linked together. It’s a common misconception that they move by electrons. Just think about transformers (two coils separated by a gap), there is a gap there but AC can travel across that gap.
You need a complete path for the electricity to travel.
An analogy with a bicycle chain. With DC, you’re constantly pedalling in one direction. The top half of the chain is always going forwards, and the bottom half is going backwards.
Now think of someone on a unicycle trying to remain roughly stationary – they do this by constantly pedalling backwards and forwards in little steps, and likewise the chain is constantly jiggling backwards and forwards. That’s AC.
The top and bottom halves of the chain are the hot/line and neutral (or whatever terminology is used depending on your country and set-up). Now think what happens if you cut the bottom half of the chain.
An analogy with a bicycle chain. With DC, you’re constantly pedalling in one direction. The top half of the chain is always going forwards, and the bottom half is going backwards.
Now think of someone on a unicycle trying to remain roughly stationary – they do this by constantly pedalling backwards and forwards in little steps, and likewise the chain is constantly jiggling backwards and forwards. That’s AC.
The top and bottom halves of the chain are the hot/line and neutral (or whatever terminology is used depending on your country and set-up). Now think what happens if you cut the bottom half of the chain.
Voltage is measured in relation to a reference. The neutral wire is your reference.
For DC, the voltage stays the same, for AC, the voltage changes from positive to negative in relation to that reference.
There are many types of electricity grids, but the neutral wire is often tied to ground somewhere.
(Edit: For multiphase systems, there is not always a neutral needed as the voltage of one phase if referenced to another phase. This video explains it: https://www.youtube.com/watch?v=zaK_dy-x00w)
Voltage is measured in relation to a reference. The neutral wire is your reference.
For DC, the voltage stays the same, for AC, the voltage changes from positive to negative in relation to that reference.
There are many types of electricity grids, but the neutral wire is often tied to ground somewhere.
(Edit: For multiphase systems, there is not always a neutral needed as the voltage of one phase if referenced to another phase. This video explains it: https://www.youtube.com/watch?v=zaK_dy-x00w)
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