Capacitors vs inductors and current vs voltage.

[Ratch]

Thank you for derailing yet another thread and filling it with off-topic posts.

Nonsense.  I only answered questions and statements presented to me.  Nothing is stopping the OP or anyone else from asking questions more pertinent to the original post.  Your assertion is bogus.

Ratch

[Brumby]

"current(noun) flow(verb)"

No, "current" in electrical science means charge flow or rate of charge movement.  If you want to use rate as a noun, then it implies charge movement, and the second word "flow" is redundant and ridiculous.  Find any sentence using current flow and see how much better it sounds using my suggestion.

Ratch

You have just proved my point about grammatical constructs.  You don't understand how language is put together.

Look up the definition of the word "current".  In that definition, you will find the usage for it in the electrical realm is as a NOUN.  It doesn't matter what words make up the definition of that quantity - those words are only used to provide information about what the quantity represents.  Once that is done, IT HAS ITS OWN EXISTENCE - as a NOUN.  Nouns can have verbs associated with them.  This is grammar 101.


This is never going to be resolved to your satisfaction - so I am going to bow out, as promised.


Doesn't mean I think you are right, though.

[Ratch]

When someone intentionally showing off how smart he is and how the conventional sayings and how ordinary people are wrong, he is either really, really smart, or really just being annoying. It's advisable not to argue with really smart people since you always lose, and also not to argue with annoying people since that's what they are after.

Would you be so kind as to explain why the above non-technical statement is showing up in this thread.  Please be specific and use examples if necessary.

Ratch

[Ratch]

"current(noun) flow(verb)"

No, "current" in electrical science means charge flow or rate of charge movement.  If you want to use rate as a noun, then it implies charge movement, and the second word "flow" is redundant and ridiculous.  Find any sentence using current flow and see how much better it sounds using my suggestion.

Ratch

You have just proved my point about grammatical constructs.  You don't understand how language is put together.

Really?

Look up the definition of the word "current".  In that definition, you will find the usage for it in the electrical realm is as a NOUN.  It doesn't matter what words make up the definition of that quantity - those words are only used to provide information about what the quantity represents.  Once that is done, IT HAS ITS OWN EXISTENCE - as a NOUN.  Nouns can have verbs associated with them.  This is grammar 101.

It is?  Do you mean that just because a word is a noun, you can couple it to any verb you like, even if it makes the phase redundant and longer than it needs to be?  Would you say "blowing wind" when you are writing correct English.  I sure wouldn't unless I was writing poetry.  "Wind" already implies blowing, so it is redundant.

This is never going to be resolved to your satisfaction - so I am going to bow out, as promised.

I am sorry you see the need to leave this thread.

Doesn't mean I think you are right, though.

I understand.

Ratch

[rs20]

Hmm, it's been a pleasant couple of months since I had come across a Ratch post.

A cap does not "charge up."  It contains the same amount of net charge at 10, 100, or 1000 volts as it does at zero volts.

                          

You did not contribute usefully to this thread. The OP's new understanding is much improved compared to his/her old understanding, but rather than recognizing that you had your utterly worthless kneejerk reaction to the use of the single word "charging". I wish you luck at teaching everyone on the planet to "re-energize" their phone batteries because they're "not recharging them" because "they retain a net neutral charge". What's your next crusade, reversing the flow of conventional current to match the flow of electrons?

[Cliff Matthews]

I read this far to find hapless pedantic  's again..

[Ratch]

Hmm, it's been a pleasant couple of months since I had come across a Ratch post.

A cap does not "charge up."  It contains the same amount of net charge at 10, 100, or 1000 volts as it does at zero volts.

                          

You did not contribute usefully to this thread. The OP's new understanding is much improved compared to his/her old understanding, but rather than recognizing that you had your utterly worthless kneejerk reaction to the use of the single word "charging". I wish you luck at teaching everyone on the planet to "re-energize" their phone batteries because they're "not recharging them" because "they retain a net neutral charge". What's your next crusade, reversing the flow of conventional current to match the flow of electrons?

Evidently, you did not read post #24 of this thread where I do discuss current direction and charge polarity.  How can you tell what the OP's understanding is?  Nowhere do I see a definitive statement from you challenging the veracity of what I said.  Therefore, I assume you are disparaging the messenger, but not the message.  The planet is a big place, so I cannot hope to point out to everyone the false meaning of their phraseology.

Ratch

[Ratch]

I read this far to find hapless pedantic  's again..

No one is forcing you to read or reply.

Ratch

[Zero999]

But when precise meanings and technical descriptions must be conveyed, then precise language should be used.

Precise and useful. To say a capacitor stores no charge when it is charged up is a precisely pointless statement. It has no value and serves no purpose.

So why do folks say a cap is charged when it is not?  Unless you mean charged with energy.  Then you might as well say energized.   Actually, what I said was a cap stores a charge on one plate and depletes the same charge on the opposite plate for a net change of zero.

Ratch

When people say a capacitor is charged, they really mean that charge has been transferred, from one plate to the other, not in or out of both plates! Why do mathematical formulae, give the charge on a capacitor in Coulombs, a unit of charge?  It is an abbreviation and is used in plenty of EE papers. No one is going to re-write them because you don't think it's specific enough.

"A capacitor doesn't like to change its voltage"
"An inductor doesn't like to change its current"

This is more or less the explanation given in textbooks and tutorials and is how I came to understand the components when I learned about them. I'm just surprised that all the explanation I've seen limit themselves to this understanding while it doesn't really say how caps maintain voltage or how inductors maintain current.

Thanks for the reply.

Yes, that's pretty much correct.

The mechanical analogy is a good one. A flywheel is like an inductor and a spring is similar to a capacitor. The same could be said with a circular canal, filled with water vs dam, with a lot of water behind it.

[Ratch]

When people say a capacitor is charged, they really mean that charge has been transferred, from one plate to the other, not in or out of both plates!

No way.  The dielectric of a good cap is impermeable to charge carriers, so the charge on one plate cannot pass to the other plate through the dielectric.  Neither can the same charges get from one plate get to the other plate through the voltage source, because there are so many other charge carriers ahead of them.  In and out is the only way to describe what is happening, and although the amount of charge movement is equal on both plates, it is not transference.  Why do you have such a hard time calling a storing of energy, "energizing"?  Charging is meaningless in this operation.

Why do mathematical formulae, give the charge on a capacitor in Coulombs, a unit of charge?

Because a coulomb (not capitalized) is a unit of charge in the MKS system.  The formulas pertain to the charge difference between the plates, not a charge in or on a cap.

It is an abbreviation and is used in plenty of EE papers.

Coulomb is not an abbreviation, it is a fully spelled out word.

No one is going to re-write them because you don't think it's specific enough.

I don't expect anything already published to be edited.  Specificity is not what I am talking about,. Accuracy is.

Ratch

[IanB]

Every part of regular circuit analysis satisfies Kirchhoff's current law, which says that there is no local accumulation of charge in a circuit: all flows of charge around any control element are balanced, in = out. Capacitors are no different, so it escapes me why you keep trying to make such a fuss about something that bothers nobody else in the world, ever.

If you discharge a capacitor then current flows in the circuit, and by your own statement current is the flow of charge. If charge flows, then there must have been a movement or displacement of charge. This is what is meant by the charge stored in a capacitor, something appreciated by everyone in the world except you. If it is you against the world, why do you keep trying? You cannot win your argument, ever. It is a futile waste of energy on your part.

[Ratch]

Every part of regular circuit analysis satisfies Kirchhoff's current law, which says that there is no local accumulation of charge in a circuit: all flows of charge around any control element are balanced, in = out. Capacitors are no different, so it escapes me why you keep trying to make such a fuss about something that bothers nobody else in the world, ever.

Many folks think caps and batteries store net charge.  They don't.  I agree that caps follow K's current law.  Who said I did not? 

If you discharge a capacitor then current flows in the circuit, and by your own statement current is the flow of charge. If charge flows, then there must have been a movement or displacement of charge. This is what is meant by the charge stored in a capacitor, something appreciated by everyone in the world except you.

Yes, current is present in a closed cap circuit when a cap is de-energized by supplying a conduction path.  However, no net current was stored in the cap.  The plates of the cap are simply rebalancing the net charge which is zero.

it is you against the world, why do you keep trying? You cannot win your argument, ever. It is a futile waste of energy on your part.

I know I cannot change the whole world.  And you have no way of knowing if I am the only one who believes a capacitor cannot hold a net charge.  I am winning this argument at this point in time because I have given a clear explanation of what I believe and no has proven my assertion wrong thus far.

Ratch

[IanB]

I am winning this argument at this point in time because I have given a clear explanation of what I believe and no has proven my assertion wrong thus far.

Because no-one cares. If there is something that bothers you and bothers nobody else, then it is up to you to learn how not to be bothered by it. Neither I, nor anyone else has any trouble with the language of capacitors. We don't have to prove your assertions wrong. We are not troubled by the notion of capacitors storing charge. For us everything is perfectly fine.

[Ratch]

I am winning this argument at this point in time because I have given a clear explanation of what I believe and no has proven my assertion wrong thus far.

Because no-one cares. If there is something that bothers you and bothers nobody else, then it is up to you to learn how not to be bothered by it. Neither I, nor anyone else has any trouble with the language of capacitors. We don't have to prove your assertions wrong. We are not troubled by the notion of capacitors storing charge. For us everything is perfectly fine.

And, most folks are happy to think that NASA astros "walk" in space.  I think it is funny and others are perfectly  fine and  happy.

However, one particular participant got confused by your way of looking at caps.  See http://www.electro-tech-online.com/threads/conservation-of-charge.151864/

Ratch

[IanB]

However, one particular participant got confused by your way of looking at caps.

Many people get confused by many things.

There are equations that describe the behavior of capacitors. If you apply the equations correctly, you reach correct conclusions. If you don't apply the equations, and instead try to argue from verbal descriptions, then you may get the wrong answer.

[Ratch]

However, one particular participant got confused by your way of looking at caps.

Many people get confused by many things.

True, but this individual got confused by applying the understanding you espouse.

There are equations that describe the behavior of capacitors. If you apply the equations correctly, you reach correct conclusions. If you don't apply the equations, and instead try to argue from verbal descriptions, then you may get the wrong answer.

Well, this individual also used equations.  But, without correct understanding, equations will still give the wrong answer.

Ratch

[Simon]

However, one particular participant got confused by your way of looking at caps.

Many people get confused by many things.

True, but this individual got confused by applying the understanding you espouse.

There are equations that describe the behavior of capacitors. If you apply the equations correctly, you reach correct conclusions. If you don't apply the equations, and instead try to argue from verbal descriptions, then you may get the wrong answer.

Well, this individual also used equations.  But, without correct understanding, equations will still give the wrong answer.

Ratch

What are you trying to achieve ? Your behaviour is the same that got another member recently banned. Splitting hairs over every word does not help anyone and disrupts the forum, and eventually will get you banned as it derails every thread!

[Ratch]

Simon,

I am simply correcting mistakes in terminology. Everything I said is true, even if you and others don't believe it.  I also give reasons and examples for what I aver. If no one is required to read or reply to what I say, how can I  disrupt the forum?  If this forum does not acknowledge different viewpoints, what good is it?   I am doing this forum a favor by imparting some true knowledge, even if there are those who don't appreciate it because it goes against what they believe.  Let them prove me wrong.  Disparaging the messenger does not change the message.

Ratch

[tooki]

Simon,

I am simply correcting mistakes in terminology. Everything I said is true, even if you and others don't believe it.  I also give reasons and examples for what I aver. If no one is required to read or reply to what I say, how can I  disrupt the forum?  If this forum does not acknowledge different viewpoints, what good is it?   I am doing this forum a favor by imparting some true knowledge, even if there are those who don't appreciate it because it goes against what they believe.  Let them prove me wrong.  Disparaging the messenger does not change the message.

Ratch

"Correcting" to a private definition at odds with the commonly-understood terminology is not correcting, nor is it educational, it's simply pompous intellectual dick-waving that distracts from the topic at hand. And it's that distraction that makes it disruptive. You aren't doing anyone any favors, as the plethora of objectors to your stupid comments show.

[Simon]

The simple answer is that if you are going to disrupt every thread by splitting hairs over terminology when everyone is clearly able to understand the concepts being discussed without confusion you will just be disrupting the forum and derailing threads and that gets you banned! and you would not be the first to be banned for this sort of behaviour. you have managed 200 posts without being brought to my attention so whatever you were doing before maybe you should go back to it. We have plenty of knowledgeable peoples on here and are very glad of their help (I am personally anyway) but they are also humble people that put their oar in when required and when it is positively helpful and they actually share information and insight instead of being walking dictionaries, being a smart ass is not helpful. I have nothing further to say on the matter, it's up to you how you conduct yourself and I can't stop people from responding to your provocations. If and when the time comes that we deem you causing more hassle than due you will be banned without further warning! It's a process that takes under a minute and far outweighs the headache that disruptive members can cause. We are a very laid back forum and try to allow for "individuality" but will NOT let that individuality ruin the experience for others, we don't have hard and fast rules but then neither does any social interaction, we expect people to use common sense.

[Ratch]

Simon,

I am simply correcting mistakes in terminology. Everything I said is true, even if you and others don't believe it.  I also give reasons and examples for what I aver. If no one is required to read or reply to what I say, how can I  disrupt the forum?  If this forum does not acknowledge different viewpoints, what good is it?   I am doing this forum a favor by imparting some true knowledge, even if there are those who don't appreciate it because it goes against what they believe.  Let them prove me wrong.  Disparaging the messenger does not change the message.

Ratch

"Correcting" to a private definition at odds with the commonly-understood terminology is not correcting, nor is it educational, it's simply pompous intellectual dick-waving that distracts from the topic at hand. And it's that distraction that makes it disruptive. You aren't doing anyone any favors, as the plethora of objectors to your stupid comments show.

Pointing out the mistakes in a definition, whether public or private, is a         
correction no matter how much you think otherwise. If pausing and evaluating what you believe is a disruption, so be it.  You have not said that my comments were false, only that you and others did not like them. I cannot help that. The facts are what they are.

Ratch

[Ratch]

The simple answer is that if you are going to disrupt every thread by splitting hairs over terminology when everyone is clearly able to understand the concepts being discussed without confusion you will just be disrupting the forum and derailing threads and that gets you banned! and you would not be the first to be banned for this sort of behaviour. you have managed 200 posts without being brought to my attention so whatever you were doing before maybe you should go back to it. We have plenty of knowledgeable peoples on here and are very glad of their help (I am personally anyway) but they are also humble people that put their oar in when required and when it is positively helpful and they actually share information and insight instead of being walking dictionaries, being a smart ass is not helpful. I have nothing further to say on the matter, it's up to you how you conduct yourself and I can't stop people from responding to your provocations. If and when the time comes that we deem you causing more hassle than due you will be banned without further warning! It's a process that takes under a minute and far outweighs the headache that disruptive members can cause. We are a very laid back forum and try to allow for "individuality" but will NOT let that individuality ruin the experience for others, we don't have hard and fast rules but then neither does any social interaction, we expect people to use common sense.

What you call splitting hairs, I believe is a major misbelief.  I gave an example of that with a link to another thread within reply #40 of this thread. The OP of that thread was definitely confused because he believed what many on this thread proclaim.

I think this forum is very uptight, not laid back as you claim.  However, let's make a deal. You keep this thread open until everyone has a chance to take a whack at me. I promise to answer to only this thread, and after it is finished, I will never post on this forum again.  If fact, I will probably never even read this forum again, so you can ban me or not. It is only fair that everyone should get a chance to express their opinion.  OK?

Ratch                                                           

[IanB]

You have not said that my comments were false, only that you and others did not like them. I cannot help that. The facts are what they are.

No-one disagrees with the statement that there is no change in the net charge on a capacitor. Everyone understands that charge removed from one plate is balanced by the charge added to the other plate.

What everyone is trying to tell you is that insisting that capacitors do not get "charged" is pointless, unfruitful, and serves no useful purpose. Nobody is arguing with your facts, but everybody is arguing that it is pointless and a waste of time to make a big deal out of it.

Consider your example of charging two capacitors and putting them in series. Each capacitor individually has a net charge of zero. Therefore when putting them in series the combined capacitor has a net charge of zero plus zero, equals zero. The answer you get is completely accurate, and yet completely useless. No useful understanding is gained from this.

[Ratch]

You have not said that my comments were false, only that you and others did not like them. I cannot help that. The facts are what they are.

No-one disagrees with the statement that there is no change in the net charge on a capacitor. Everyone understands that charge removed from one plate is balanced by the charge added to the other plate.

What everyone is trying to tell you is that insisting that capacitors do not get "charged" is pointless, unfruitful, and serves no useful purpose. Nobody is arguing with your facts, but everybody is arguing that it is pointless and a waste of time to make a big deal out of it.

Consider your example of charging two capacitors and putting them in series. Each capacitor individually has a net charge of zero. Therefore when putting them in series the combined capacitor has a net charge of zero plus zero, equals zero. The answer you get is completely accurate, and yet completely useless. No useful understanding is gained from this.

Yes, the charge balance evens out.  There is a dichotomy in your reasoning.  How can an accurate answer be completely useless?  The OP of that thread certainly gained some understanding.  He even said he liked my explanation.

Ratch 

[Zero999]

When people say a capacitor is charged, they really mean that charge has been transferred, from one plate to the other, not in or out of both plates!

No way.  The dielectric of a good cap is impermeable to charge carriers, so the charge on one plate cannot pass to the other plate through the dielectric.

That was never implied. You made that up.

Neither can the same charges get from one plate get to the other plate through the voltage source, because there are so many other charge carriers ahead of them.  In and out is the only way to describe what is happening, and although the amount of charge movement is equal on both plates, it is not transference.

The electromotive force applied to the capacitor, moves charges through the conductors, causing an imbalance in charge, between the plates of the capacitor. The fact that they're not exactly the same charge carriers is immaterial.

  Why do you have such a hard time calling a storing of energy, "energizing"?  Charging is meaningless in this operation.

Because it's meaningless, non-standard terminology. "An electric fence is energised" and "One should be careful when working on energised mains circuits" are examples of how the word energised is normally used in electrical engineering. The only time I think I've seen energised used in the context of capacitors is in a safety manual, on the lines of "Take care when working with circuits, containing capacitors charged to hazardous voltages. The circuit can remain energised for a considerable length of time, after the mains power has been isolated."

The formulas pertain to the charge difference between the plates, not a charge in or on a cap.

And that's what people mean by charging a capacitor. They're referring the difference between charge on the plates. The same principle applies to when one mentions battery voltage. Why do you have such a hard time understanding these very basic concepts?

Everyone knows about the conservation of charge and that batteries and capacitors never ever gain or loose any net charge. All you're doing is creating confusion and derailing the thread.