Relation

One eV is the energy gained by an electron or proton when it is accelerated by a voltage drop of 1V.

Numerically,

Mark

If you mean eV, or electron volts, it's a unit of energy. It's the energy associated with a single electron moved through one volt of potential difference. Moving a charge of 1.6E-19 Coulomb (one electron or proton) through one volt requires or gives up an energy of 1.6E-19 Joules. That's the relationship: charge * voltage difference = energy. More at...

-- john

joules = coulombs * volts = ( amperes * seconds * volts )

electon_volts = electrons * volts

coulombs = electrons * 0.00000000000000000016021892 (approx)

joules = electron_volts * 0.00000000000000000016021892 (approx)

To put this another way. the electrons in the electron beam inside a CRT that's operating at 30000V are each hitting the front of the screen with an energy of 30000eV

Hope that helps.

Bye. Jasen

Doesn't the energy increase over time as the electron is accelerated ? Or is it the energy gained by the electron when it travels across the voltage drop ? In this case, does it mean that the energy is always the same whether the drop is across 1m or 1mm ?

vic

Do you remember the speed of electricity in copper? Was it 1/2 light speed?

The time is really irrelevant; it's the change of location of the charge within the potential field that matters.

If the charge is allowed to free-fall through the field, it will pick up a kinetic energy equivalent to the potential difference between the starting point and ending point of its trajectory within the field. It's similar to masses moving about in a gravitational field, where potential energy is a matter of location within the field.

'Speed of electricity' ?

You really are a case and a half you know !

Graham

"Eeyore" a écrit dans le message de news: snipped-for-privacy@REMOVETHIS.hotmail.com...

speed?

Graham, I've measured it, and it is about one third. That is it takes 0.3s for me to say 'light' and 1s to say 'electricity'.

At 1/3 he wasn't far off, but I agree that saying that in copper is another matter.

Never mind, I asked metacrawler (my search engine) about "speed of electricity" and got 91 hits and NO chickenshit from nincompoops who think electricity doesn't have a measurable speed. I'll be checking out the opinions of people who have better things to do than flame their betters to try to save their faces.

speed?

Yes. But for a given set-up, there is only one time at which the electron is at a potential of 1V (relative to the starting point).

That is correct also.

Yes.

p.s. I guess it would be more proper to say 1 eV is the work done on the electron when it moves through a potential of 1 V. This would apply both to an electron in a vacuum tube (where the work becomes kinetic energy of the electron) as well as an electron moving through a resistor (work is transformed into heat).

Mark

I kinda like this answer, especially the note on the bottom. The term Q in the equation seems to relate the speed to the type of material. BTW light doesn't travel at the speed of light (in a vacuum) when it encounters a "transparent" material. This is for any of you dorks who were going to try to tell me that electricity travels at the speed of light.

--------------------------------------------------------------------- Posted by killians45 on 01-26-2005 05:44 PM:

actually, I am as fast as the speed of light... maybe a little faster... anyhow, back to the question. Electric current is slow moving and actually almost sits there and vibrates (thus exciting from one electron to the other). Energy flow, on the other hand, is very fast (and yes, there IS a difference). To say how fast is rather hard, because the speed of the energy flow is related to the value of the current... small current = low speed energy flow and vice-a-versa. That's just one thing that affects the speed. The size of the wire (listed above) also does. To find out the speed have to know the amperes, wire diameter/radius, and how many moving electrons per cubic centimeter. Once you have this the formula is:

I = amperes D = wire diameter Q= moving electrons per cubic centimeter e = charge per electron

cm/sec = I / Q x e x R ^2 x pi

this is for DC

__________________ If you argue with an idiot he will drag you down to his level and beat you with experience.

speed?

There are two concepts involved here. The model I like to use to explain this is to imagine a pipe (wire) full of marbles (electrons). If you push a marble into one end of the pipe, a marble comes out the other end "immediately". Even though individual marbles may move very slowly, they are all touching so the "information" or "energy" moves at the speed of sound. And so it is with electrons in a wire; the actual speed of any electron is pathetically slow in most cases (you could probably walk faster), but the speed of "electricity" is close to the speed of light.

Best regards,

Bob Masta dqatechATdaqartaDOTcom D A Q A R T A Data AcQuisition And Real-Time Analysis

On Fri, 04 Aug 2006 12:00:11 GMT, in message , scribed:

Yes, well, it would be helpful if you would actually read any of the articles that were returned by your web crawler. When you do, you may see how silly your original question - as well as this response - looks. Given your previous intransigence on matters where you were clearly in error, it should be without surprise that you see that you are being flamed on yet another mis-step.

Immediately you make a disclaimer that says you will ignore anyone who disagrees with you. This comes attached to the fact that the only evidence you offer that there is a such thing as "speed of electricity" is that the phrase returns hits on a web search. Well, I did a Google search on "Moon made of green cheese" and got 478 hits, which by your logic seems to show that it is 5.25 times more likely that the moon is made of green cheese, than there is such a thing as "speed of electricity." You're up, mate, and I've got a wager placed on your response. It's a complex wager, with several variables, so don't disappoint, alright?

On Fri, 04 Aug 2006 12:50:05 GMT, in message , scribed:

The speed of what, exactly?

Who, precisely please, in this forum, ever said such a thing?

Did you read this quoted passage?

This part of the quote is probably the most apropos statement with regards to follows-up to your posts.

OK, I've asked three simple questions. Do you have what it takes to simply answer them, without the troll's recourse to obfuscation, misdirection, and insult? I bet not. After all, you're still unable to stop top-posting. It's such a simple thing, really, yet you're not able to grasp the concept.

Alan, either come up with a number AND a workable methodology for arriving at that number or STFU. You have already proved to me that you are very good at coming up with excuses why YOU can't do something, but fail miserably at finding ways to accomplish something.

ns le

er

Thank you, thank you, thank you Velocity Factors up to 95 for ladder line and down to 66 for RG-58. REAL NUMBERS! HOORAY!

le

another

You're too late, "thepackrat741" already got the first prize, "Bob Myers" came in second, and the rest of the participants can console themselves by kissing my butt.

think

Unfortunately, "speed of electricity" isn't a precise enough phrase to narrow down what you're really after. Do you want to understand how electrical energy propagates through conductors (if so, that's where things like the "velocity factor" come into play), or do you want to know how fast the individual electrons themselves move through the material? These two are not at all the same.

Bob M.