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which makes more sense to you about Volts?

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KevinAlaska

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when talking about voltage I have heard/read people mention pressure and at times speed of electrons with the water analogy.

But to me I think they should use a person walking (current) with more people walking would be (amp).

Resistance would be opposition to them walking like a head wind. or walking through sand or mud etc.

Volts would be something like the strength of the walking people. If they are strong men then they can walk through the resistance easier with less of a problem. If they are week (lower voltage) then they have a harder time walking though.

But the speed of which they walk through is not effected only how hard they have to try to move through this resistance.

Because in reality electrons move no faster or slower. Isn't that correct?

Sincerely,

Kevin in Alaska
 
Electrons don't move faster or slower (for all intents and purposes, of course things can vary in nature a bit though...).

THe analog I use is the pressure of water in the pipe is the voltage, and the flow rate of the water in the pipe is the current. if the water pressure isn't high enough to push through the narrow pipe, then not all of the water gets through. Simple as that.

Nothing about the water getting slowed down because it can't push hard enough or whatever (sometimes used in the car-in-a-tunnel analogies). Those just confuse people because it implies electrons move more slowly in the resistor than in the wire. This would cause a build-up of electrons inside the resistor until it exploded, in the same way a funnel overflows if you pour water into it too quickly.

It's similar to your strong men analog, except the current is the number of men going through the doorway at once, rather than the weaker ones getting slowed down. If you can't push hard enough you don't get through at all.

I like using the flow-rate of water or the number of men going through the door at once because it explains how current can be split down two wires and why voltage is the same across parallel connections (there is a loophole to this analogy though with parallel resistors of different values.)
 
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KevinAlaska said:
when talking about voltage I have heard/read people mention pressure and at times speed of electrons with the water analogy.

But to me I think they should use a person walking (current) with more people walking would be (amp).

Resistance would be opposition to them walking like a head wind. or walking through sand or mud etc.

Volts would be something like the strength of the walking people. If they are strong men then they can walk through the resistance easier with less of a problem. If they are week (lower voltage) then they have a harder time walking though.

But the speed of which they walk through is not effected only how hard they have to try to move through this resistance.

Because in reality electrons move no faster or slower. Isn't that correct?

Sincerely,

Kevin in Alaska

Great analogy Kevin!

In my text box they used dump trucks however.. to portray volts they used the amount of 'energy' in the trucks pale..

More payload.. more voltage.
 
Voltage is potential difference, put simply the number off excess electrons in one region relative to the deficiency of electrons in another region.

Current is the number of electrons flowing though a conductor per second.

Now although what I've said above isn't strictly true, as I can't remember the constants but 1V is a hell of a lot of electrons in one region relative to another and 1A is a hell of a lot of electrons per second.
 
Voltage is more like height or altitude. Current flows from top to bottom. You can specify the top level of a mountain as the height referenced from its base, or as the altitude referenced from sea level. A basement level in a building is below ground level. A generator or power source pumps out current at the top and pulls it in from the bottom.

A conductor with a varying voltage would be like a rigid horizontal pipe that moves up and down (without changing its horizontal attitude).
 
If my calculator is working properly, a columb (one amp/second) is the equivilant movement of 62,415,096,291,526,500,000 electrons.
 
Almost, but:
a columb (one amp/second)
should be
I = Q/t; one amp = one coulomb/one second
one coulomb = 6.25 x 10^18 electrons,
so "62,415,096,291,526,500,000 electrons" per second
 
Isn't it 6.25x10^19? Or was that 10^19 a part of a couple other constants? Don't remember anymore.
 
BeeBop, Peter. Funny, that's the same thing I said =)

dknguyen. I think it's 1.6x10^-19 is the reciprocal.
 
The real fun part comes into when you have to figure out the environment and distances that those electrons move in. A columb of electron movement through a 1 inch diameter copper rod is very different from say the movement of the same number of electrons through a 30 gauge wire. All of the EM parameters change with number of charge carriers voltage potential and distance are increased.
 
I think it's 1.6x10^-19 is the reciprocal.

Yes, that is true, but look again at what you said:
a columb (one amp/second)
That isn't right. Current depends on time. A coulomb is a quantity.
You worked it out right, but your English was wrong. I'd have gotten a big red zero from my teacher!
 
Sceadwian said:
The real fun part comes into when you have to figure out the environment and distances that those electrons move in. A columb of electron movement through a 1 inch diameter copper rod is very different from say the movement of the same number of electrons through a 30 gauge wire. All of the EM parameters change with number of charge carriers voltage potential and distance are increased.

That just comes down to resistivity; if we really want to have fun with it, then we should start with a sine wave passing through several lengths of different conductors in parallel, in and environment where the temperature is constantly changing. :)
 
I've found water variables to help communicate electronic current flow to newcomers useful sometimes. I keep it simple using voltage = pressure, current = flow quanity and resistance = pressure drop.

Lefty
 
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BeepBop, a columb is defined as one ampere per second. It's a quantity of electrons over time, not so sure it's my english that needs work =)
 
has anybody ever seen (I think it was 1000 amps, not sure) 1000 amps go through 24 gauge wire? KA BOOM!
 
Sceadwian said:
BeepBop, a columb is defined as one ampere per second. It's a quantity of electrons over time, not so sure it's my english that needs work =)

Hey Sceadwian,

Im going to have to disagree wtih you.

A columb is just a large 'packet' or electrons 1.6 x 10^18 (as talked about above)


1 amp = 1 C / 1 Sec

If we rearrange the above formula for Columbs:

C = A X Sec

So do we call this Amp Second?

A columb is defined as one ampere per second

Where did you see this?
 
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Sceadwian said:
BeepBop, a columb is defined as one ampere per second. It's a quantity of electrons over time, not so sure it's my english that needs work =)
Sceadwian (I'm still trying to figure out how to pronounce this one!) then it isn't your English, but your concept. It's a fact, so don't take my word for it, go look it up.
 
Leftyretro said:
I've found water variables to help communicate electronic current flow to newcomers useful sometimes. I keep it simple using voltage = pressure, current = flow quanity and resistance = pressure drop.

Lefty

Always worked for me, too. :)
 
BeeBop....

Columbia Electronic Dictionary "coulomb [for C. A. de Coulomb], abbr. coul or C, unit of electric charge. The absolute coulomb, the current U.S. legal standard, is the amount of charge transferred in 1 second by a current of 1 ampere; i.e., it is 1 ampere-second. "

Wikipedia "
Coulomb

Wikipedia, the free encyclopedia - Cite This Source

The coulomb (symbol: C) is the SI unit of electric charge. It is named after Charles-Augustin de Coulomb.
Definition

1 coulomb is the amount of electric charge transported by a current of 1 ampere in 1 second. "


Crystal Refrence Encyclopedia "
Coulomb

Crystal Reference Encyclopedia - Cite This Source


[koolom] SI unit of electric charge; symbol C; named after Charles Coulomb; defined as the quantity of electricity transported by a current of 1 ampere in 1 second."

Before you tell someone to look something up, it's generally a good idea to look it up yourself.

Sceadwian's a word based off old english so I'm not even sure how to go about the 'proper' pronounciation if there is one.
 
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