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> why do you get sparks when the B and W wires touch each other...?
Because electric wants to travel from black to white. Black is the top half of the hill. White is the bottom half. We put loads in the middle.

so this is the wave form or sine wave thing? just looks like a hill on top of the line and an inverted hill under the line? if thats right then it appears that the white wire could have as much current on it as the black wire? in fact if this is the picture i have in my mind, then it looks like the 2 hills are always the same size??
how do you make bold type as a reply to my message?

>so this is the wave form or sine wave thing?
Sorry, no. The wave form has next to nothing to do with this. Please disregard any such inference.


>how do you make bold type as a reply to my message?
It's tough to explain. But there are bracket-boxes with B and /B in them around the bold text. Click on the edit icon (the one with the pencil) for my message and you can see how I put in the UBB codes. You can see how people put in faces too this way.


[This message has been edited by Dspark (edited 06-23-2001).]

>so if i use the water analogy some more here, you are calling the electrical pressure voltage like the water pressure in a hose maybe, but its still water, or current, or electricity, you are just describing it in different terms, maybe?
Yeah!

>after the hose is turned on and runs the sprinkler or whatever then just less of the water, or voltage ..., is left to deal with maybe?
Yeah, no water (current) is lost. It wants to get back to the ground.

>if the 120 volts in the black wire just goes straight through the fan or something
It doesn't exactly. The fan prevents much from flowing and it extracts power from the current.

>so does that mean that the white wire is never supposed to be able to let that much current or voltage go back to the ground or transformer or ground bus you referred to?
It's the device (fan, light, etc.) that impedes the path of the electricity. If you cross black with white with nothing in between, it will trip the CB.

>it sounds like the white wire has current whenever something is turned on,
Right.

>but not as much as the black wire
Same amount, exactly - just most of the power has been extracted.

Perhaps you would find a website on the topic to be interesting?
http://www.howstuffworks.com/power.htm
http://www.epelectric.com/apogee/foe_html/home.htm


[This message has been edited by Dspark (edited 06-23-2001).]

>it sounds like the white wire is also hot when the fan or whatever is running, maybe just not as hot as the black, maybe, is that right?
Kind of. The white wire has current flowing in it. The white wire is its best hope for getting back to the transformer where it wants to be. If you touch it, and you offer it a path, it will take it. But a human is a lousy path compared to the white wire which is a metallic path straight back to the transformer.

Now when you touch the black wire, it's a different story. There is more current available there than can get by via the light bulb or whatever because the light bulb offers resistance and limits how much current can flow. So there is current available on the black wire waiting for any possible means to get back to the transformer.

If you touch the black wire, as much current as can travel through you will do so limited only by the amount of resistance you offer.
(On the white side, you are competing with a copper wire

OOOOOOOOOOOOhhhhhhhhhhhhhhhhhh
duhhhh, i get it, the black wire is just the stored energy like a balloon blown up or water in a hose or a suspended weight, waiting for a way to release all of that pent up energy by getting to the transformer, and the white wire is made to be a very easy way to get there as opposed to going through me with more resistance then back into the white wire to the transformer. sorry i'm picking this up sorta slow, but the wave hill thing is not working for me too well yet. the sine wave is just a representation of the presence of current or voltage? if the top is hot and the bottom is neutral compared to the hot where the hot side is being pushed and the neutral side is being pulled then it doesnt seem like it would ever change whether there was a fan load or not in the middle. maybe i have this pictured wrong. it just seems like what goes out and back on these wires would balance out and look the same with the equal amounts on top and below, going and coming.
i talk too much so dont worry about replying if i'm too far out in left field thanks

one other thing though, sorry
>if the electricity alternates back and forth from the black wire through my stuff and back over the white wire
The white side is there passively (we call it neutral).
The black side is doing the pushing and pulling. So while it is true that the current alternates, power is coming from the black side only. (It's not like the black side pushes then the white side pushes it back.)
so this means like i said, i hope, that the black wire current still travels on the white wire because it wants to go back to the transformer that way, but its not like its really going that one direction from the black to the white, because you said that it alternates, as in a.c. alternating current. so i keep coming up with this dumb question about how come there could be more current on the black wire when it is alternating back and forth from the source through the black wire and load and white wire and to the transformer which is where it came from to begin with i assume. some how it seems that it should be equal on both the white and black since it alternates, but i remember making sense of a comment i made a little while ago that it made sense that there was more current on the black wire because after going through the fan there wasnt as much current remaining to come out on the white wire. one of me is wrong

WOW! that was a book, opps

just took a breath and reread some things:

When the appliance or other load is "on", there's just as much electrical current flowing through the neutral as is flowing through the hot. What's different is the "pressure" or voltage behind the current. There's less "push" or voltage on the neutral side of the load because the load has used that energy to do whatever it does.

to summarize:
1. Forget what i said about the wave thing, i misunderstood.
2. The current IS the same on the hot and neutral for the fan.
3. The voltage pressure is less on the neutral side of the fan.

[This message has been edited by Cindy (edited 06-23-2001).]

>i get it, the black wire is just the stored energy like a balloon blown up or water in a hose or a suspended weight, waiting for a way to release all of that pent up energy by getting to the back to transformer, and the white wire is made to be a very easy way to get there as opposed to going through me with more resistance then back into the white wire to the transformer.
You probably get it. But that energy is released all along the trip. Most of it is consumed the the load (light, fan, motor, etc.).


>but the wave hill thing is not working for me too well yet.
I think I can help you a little with that.

The sine wave merely means the the black side varies between pushing really hard, pulling really hard, and everything in between.

>the sine wave is just a representation of the presence of current or voltage?
Voltage. But if flowing, current flows in proportion to voltage, so for a simple resistive load like a lamp, the current also has the same wave.

>if the top is hot and the bottom is neutral compared to the hot where the hot side is being pushed and the neutral side is being pulled then it doesnt seem like it would ever change whether there was a fan load or not in the middle. maybe i have this pictured wrong.
I think so. Perhaps if you just forget about the pulling half for a while it will help.

>it just seems like what goes out and back on these wires would balance out
And indeed it does. Completely.

>and look the same with the equal amounts on top and below, going and coming.
Yes.

>so this means like i said, i hope, that the black wire current still travels on the white wire because it wants to go back to the transformer that way, but its not like its really going that one direction from the black to the white, because you said that it alternates, as in a.c. alternating current.

This is tough for me. The black is the source of the push and the pull. Both do useful work.

>how come there could be more current on the black wire when it is alternating back and forth from the source through the black wire and load and white wire
There can't be.


>and to the transformer which is where it came from to begin with i assume.
Correct.

>some how it seems that it should be equal on both the white and black since it alternates,
Good. Because you got that much right.

> there was more current on the black wire because after going through the fan there wasnt as much current remaining to come out on the white wire.
You just need some different words.
There is less power. And since the current on the white wire already has a good girlfriend (the white wire), it barely looks at you.

The potential current on the black wire is available and looking and desperate (sorry!).

>There's less "push" or voltage on the neutral side of the load because the load has used that energy to do whatever it does.
Not exactly.

>The current IS the same on the hot and neutral for the fan.
Yes.

>The voltage pressure is less on the neutral side of the fan.
Mainly because the white wire provides a free path back to the transformer and secondly because the load impedes the flow of additional current.

However, if you snipped the white wire, the voltage available from it would rise to the level of the black wire. In other words, it would be looking for any way at all to get back home.

Stick with the water analogies-they are the easiest to visualize and compare to electricity at a basic level.

Current = Gallons
Voltage/Potential = Pressure
Ohms/resistance = Water pipe size

When there is a gallon of water coming out of a hose and spraying you, this can be dangerous. (Imagine if you will those giant hoses used to tame riots)

But if the water is just sitting in a bucket(no pressure) it is not dangerous to you. (Disregard the temperature of the water)

So the hot/black wire is the hose and the white wire is the bucket.

To understand electricity(at least AC) any further, I think it is important to understand magnetism and how it causes electrons to flow.

Get a book on electronics basics. That is the best place to start. Trying to pick up bits and pieces from a bulletin board may have you believing something that is incorrect. The locations within the circuit are vital in understanding voltage and current.

The white wire may be at the end of circuit or it may be in the middle. This will make a difference in the dangers associated with touching the wire.

This is not a simple subject and somethings involved with electricity even good electricians and engineers don't understand.

Just want to urge caution in doing any type of electrical work if you're not 100% sure you know what you are doing. Your life is worth more than the couple hundred bucks it will cost hire a qualified electrician. P.S. Make sure your electrician gets a permit and calls for an inspection and shows you the report from the municipality saying the work is approved, if you ever need to get work done.

coulombs = gallons
current (coulombs per second) = flow

Cindy go outsdide, turn on the water faucet/volts, see the water flowing out/current. Now grab the hose in the center and crimp it/resistance, notice the flow/current reduce.

But there is much more than that to electricity, if you have 0 resistance in electricity the current would go to infinity without CB's. That's how you get electrical fires.

I got a good friend that knows everything (well within reason) electrical, even better than my father did, and that's saying plenty. But my Greek friend could not explain a thing understandable to me.

I also had an instructor that taught electricity well, but in the real world he would get you killed.

So take this info as good conversation and not as a tool for exploration.