Adding addition light and switch. Lamp only receiving 80v

[JohnW2]

True, though doesn't really invalidate Bas's statement. My physics teacher at school said the speed of an electron was about a furlong a fortnight, and then went on to show the workings of a reasonable example. (I had a lot of respect for that guy.)

Very true, but the speed with which a (different) electron pops out of the other end of a conductor when one pushes one into one end (which is what 'external observers' might perceive as 'the speed', since they can't tell one electron from another) is very much more impressive (and a very large number if expressed in furlongs per fortnight )!

Kind Regards, John

 

[EddieM]

I guess but go means to travel or move to another place. But arguing semantics is childish and not something you ever see on this forum

 

[EddieM]

Very true, but the speed with which a (different) electron pops out of the other end of a conductor when one pushes one into one end (which is what 'external observers' might perceive as 'the speed', since they can't tell one electron from another) is very much more impressive (and a very large number if expressed in furlongs per fortnight )!

Kind Regards, John

I'm not actually sure even that happens. From what I understand (and I fully accept I may well be wrong) in an AC circuit they don't move at all but vibrate back and forth slowly. The wave front however moves very quickly.

 

[JohnW2]

I'm not actually sure even that happens. From what I understand (and I fully accept I may well be wrong) in an AC circuit they don't move at all but vibrate back and forth slowly. The wave front however moves very quickly.

I was actually think/talking about DC. In terms of AC, I think what you say is correct, but that 'vibration' presumably manifests itself as a tiny bit of movement in and out of each end of the conductor.

In other words, if you look at just one half-cycle of AC (starting at the zero crossing point), it is effectively DC, and so behaves exactly the same as DC - the only difference being that an electron which 'slightly pops out' of one end (or slightly 'pops into' the conductor at the other end) during one half-cycle goes back to where it came from during the next half-cycle, and so on.

It's fairly easy to visualise/conceptualise these things (in relation to either DC or AC) if one thinks in terms of, say, a long tube filled with a line of balls in contact with one another.

Kind Regards, John

 

[EddieM]

Yes, a bit like a newtons cradle

 

[EddieM]

I personally visualise it as a river. The greater the gradient the higher the voltage and the greater the volume of water the higher the amps. A crude and simplistic analogy I accept.

 

[JohnW2]

I personally visualise it as a river. The greater the gradient the higher the voltage and the greater the volume of water the higher the amps. A crude and simplistic analogy I accept.

Sure, rivers (or even hosepipes) are a good way of visualising the effects of voltage, potential differences and current flow etc.. However, when it comes to thinking about what electrons do (or don't) get up to, the 'balls in a tube' analogy seems (at least, to me) to be more appropriate.

I suppose the most important thing is that it makes us think about what we mean (or perceive) by 'speed'. You described the issue as 'semantic' (which is probably true in terms of definitions), but I think that, in practice, it's more of a conceptual matter. If doing something (e.g. pushing a ball in) at one end of a mile-long tube causes something to happen (e.g. a ball peeping out) at the other end 'almost immediately', then many will regard that as 'very high speed' ('transmission'), even if the ball were pushed in very slowly. There is, of course, a 'very high speed', but it is the speed of transmission of the 'wave', not of the balls themselves.

Kind Regards, John