Which capacitor is more powerful?

[trnqk7]

Woolly thinking? Most people do not know or care what a vector is or does. They want a simple explanation that they can understand-not an explanation that goes over many (not all, I do in fact have a EE degree) people's heads and merely makes them feel overwhelmed. What I said may not be "technically accurate", but for the purposes of discussion with the vast majority of the population, it is more than accurate enough and more than likely, is soemthing that they will actually understand enough to be able to describe it to others. An think about the very wording you used-"A charge is static. Just like the charge in a battery, until you draw current, the the charge falls." Well, you just described a static quantity as changing...which would make it not static. If the charge falls when current is drawn...would you not associate then that current is the charge? Or more specifically, electrons are the charge, and since electrons make up current (kinda by definition) then charge is current and current is charge! Specifically, current (i) = dQ(change in charge)/change in time. I don't think most people want to get into calculus on the forums, so it is simple enough and fairly accurate to say that current = charge.

 

[Halon451]

I don't know where you got your EE degree from, but in all of my training, education and experience with electricity and electronics, "charge" aka "potential" aka "voltage" are interchangeable, meaning that you have a buildup of electrons at one point, relative to another, and until you place a conductive medium between the two (i.e., copper wire for example), you have a discharge of electrons from the point of higher potential (voltage) to that of lower potential, thereby creating a flow of electrons, as TLS Guy correctly stated, having both direction and magnitude, otherwise known as a vector. This is known to many as current.

Granted, this is all basic electricity 101 here - and fundamental knowledge that I would presume anyone with an EE would know like the back of his hand. I just wanted to state for the record that I have NEVER referred to current as 'charge', because I feel that it is technically inaccurate, and wanted to state my reasons why.

 

[Halon451]

Furthermore, I don't see anything wrong with explaining things the actual way there are, for the purpose of educating someone correctly on the matter, rather than filling their head with rubbish. There are many other ways you can explain something technical to those non-technically inclined, either make analogies, break it down into pieces, or what have you.

I don't agree with the idea of giving false information just because it makes it easier to understand. False information is false information, either way you slice it.

 

[trnqk7]

I never said it was entirely accurate-I said it was accurate enough for those without an EE degree, of which there are many. I agree whole-heartedly with your description, my point is that TLS was being extremely nitpicky about an explanation that wasn't intended for a university or professional setting-it was for anybody and everybody to be able to quickly understand without introducing a ton of new words and concepts into their lives that they didn't necessarily ask for.

 

[trnqk7]

False b/c it skips a step, the movement of that charge over a period of time in order to not introduce a term that would be new to many...sorry for keeping it simple. If you'll notice, I did include the equation for current... I=dQ/dt. I doubt most people know or care what that means unless they have some electrical background, but I see that you are from the same cloth as TLS.

 

[Halon451]

point still being, that what I said is not inaccurate-since current is defined by coulombs, saying that a capacitor holds more current is not inaccurate and is more likely to be understood by those who don't hold EE degrees.

That is not accurate, sorry. A capacitor holds a charge. A capacitor, by definition resists changes in voltage, as previously stated. An inductor on the other hand, will oppose a change in current, and might more likely fit your description.

 

[TLS Guy]

Woolly thinking? Most people do not know or care what a vector is or does. They want a simple explanation that they can understand-not an explanation that goes over many (not all, I do in fact have a EE degree) people's heads and merely makes them feel overwhelmed. What I said may not be "technically accurate", but for the purposes of discussion with the vast majority of the population, it is more than accurate enough and more than likely, is soemthing that they will actually understand enough to be able to describe it to others. An think about the very wording you used-"A charge is static. Just like the charge in a battery, until you draw current, the the charge falls." Well, you just described a static quantity as changing...which would make it not static. If the charge falls when current is drawn...would you not associate then that current is the charge? Or more specifically, electrons are the charge, and since electrons make up current (kinda by definition) then charge is current and current is charge! Specifically, current (i) = dQ(change in charge)/change in time. I don't think most people want to get into calculus on the forums, so it is simple enough and fairly accurate to say that current = charge.

It is not accurate at all to say current equals charge. I don't have an EE degree. We are talking grade school physics here. No need for calculus. I have been on these forums long enough to know that if these sort of inaccuracies are not corrected, you end up with the most outlandish statements and conclusions.

You statement sir, is grossly inaccurate and can not be allowed to stand.

 

[trnqk7]

As I just said, apparently, screw me for leaving out a step in order to keep it simple stupid (KISS method?). I've posted the actual equation for current twice now. It's there for those who understand it. There's also a simpler explanation that quite honestly, is good enough for a majority of people.

 

[Halon451]

False b/c it skips a step, the movement of that charge over a period of time in order to not introduce a term that would be new to many...sorry for keeping it simple. If you'll notice, I did include the equation for current... I=dQ/dt. I doubt most people know or care what that means unless they have some electrical background, but I see that you are from the same cloth as TLS.

I just like to present information correctly, that's all trnqk7. The OP asked a legitimate question that needed a technical answer, what's the problem?

Not trying to jump on you man for the sake of jumping on you. I can tell you're educated on the matter, I just don't agree with "dumbing it down" so everyone can understand it - I would rather bring those who don't up to speed.

 

[trnqk7]

You also can't fully describe what is going on with out calculus and derivatives b/c it is time varying...again, I=dQ/dt. A derivative. Not something from "elementary" physics. Maybe high school physics. So, without getting into a full explanation of the very makeup of electricity in general, my explanation is simpler and means just as much if not more to more people I would guess. But if you want to stir the pot and complicate things, be my guess. I've noticed it's a routine of yours.

 

[Halon451]

You also can't fully describe what is going on with out calculus and derivatives b/c it is time varying...again, I=dQ/dt. A derivative. Not something from "elementary" physics. Maybe high school physics. So, without getting into a full explanation of the very makeup of electricity in general, my explanation is simpler and means just as much if not more to more people I would guess. But if you want to stir the pot and complicate things, be my guess. I've noticed it's a routine of yours.

Thanks, I appreciate the sentiment. I think both TLS's and my own description were both accurate and simple to understand without involving complex mathematics. So, who is trying to complicate things here?

 

[TLS Guy]

As I just said, apparently, screw me for leaving out a step in order to keep it simple stupid (KISS method?). I've posted the actual equation for current twice now. It's there for those who understand it. There's also a simpler explanation that quite honestly, is good enough for a majority of people.

Physics again!

The capacitance in Farads = the charge in Coulombs/ the voltage.

So the charge in Coulombs = the capacitance x the voltage.

Lets take a look.

0.022F x 71V = 1.562 Coulombs

0.0022F X 200V = 0.44 Coulombs.

So the 22,000uF takes the prize.

Now you can not exceed the voltage rating of a cap and that means peak voltage not RMS. In fact if you don't want trouble you leave a little margin.

Now what is simpler than that? Few words and elementary school math.

It answered the original question accurately and PRECISELY. Before that the question was not definitively answered. That's all I have to say on the matter.

 

[trnqk7]

I just like to present information correctly, that's all trnqk7. The OP asked a legitimate question that needed a technical answer, what's the problem?

Not trying to jump on you man for the sake of jumping on you. I can tell you're educated on the matter, I just don't agree with "dumbing it down" so everyone can understand it - I would rather bring those who don't up to speed.

Fair enough, I can appreciate that. Sorry if I got a little hostile towards you. I just feel the pain of others when some posters (including ones not even participating in this thread) leave big, long-winded explanations that beg more questions than they answer b/c people can't understand all the technical stuff. There are several threads I've had a hard time following b/c of this and I went to school about it! I can't imagine how others feel, but I try, and that's why I wanted to present a simple explanation that would be "good enough" hopefully for more people.

I understand not wanting falsehoods to propagate through the community and am all for it, but, as mentioned by others before me, the same questions get asked over and over...why is this? Several reasons, but I think that one of them is overly technical explanations that go into more detail than needed to answer surprisingly basic questions many times. Why the overkill if they don't understand it? Let's keep it simple and maybe more people will understand...and if they want to know more, then they can ask.

 

[trnqk7]

Physics again!

The capacitance in Farads = the charge in Coulombs/ the voltage.

So the charge in Coulombs = the capacitance x the voltage.

Lets take a look.

0.022F x 71V = 1.562 Coulombs

0.0022F X 200V = 0.44 Coulombs.

So the 22,000uF takes the prize.

Now you can not exceed the voltage rating of a cap and that means peak voltage not RMS. In fact if you don't want trouble you leave a little margin.

Now what is simpler than that? Few words and elementary school math.

It answered the original question accurately and PRECISELY. Before that the question was not definitively answered. That's all I have to say on the matter.

And I never said this explanation wasn't good or accurate. I think it is just that, good and accurate. I was upset by your (I felt) unnecessary comment towards my post. If you were so correct and you posted your solution after me-why did you feel it necessary to pick on mine and single me out? Maybe you just have a dry/sarcastic streak in you that I do not appreciate fully, but I've noticed you do this to a lot of people. I for one am just trying to stand up for myself.

 

[Halon451]

Fair enough, I can appreciate that. Sorry if I got a little hostile towards you. I just feel the pain of others when some posters (including ones not even participating in this thread) leave big, long-winded explanations that beg more questions than they answer b/c people can't understand all the technical stuff. There are several threads I've had a hard time following b/c of this and I went to school about it! I can't imagine how others feel, but I try, and that's why I wanted to present a simple explanation that would be "good enough" hopefully for more people.

I understand not wanting falsehoods to propagate through the community and am all for it, but, as mentioned by others before me, the same questions get asked over and over...why is this? Several reasons, but I think that one of them is overly technical explanations that go into more detail than needed to answer surprisingly basic questions many times. Why the overkill if they don't understand it? Let's keep it simple and maybe more people will understand...and if they want to know more, then they can ask.

It's no problem dude, I've got thick skin. I agree that a lot of times, people do post ridiculously technical answers to seemingly simple questions, maybe just to stroke their own ego - I don't know. I've been both a student and a teacher on these matters, and I can tell you honestly, that the best approach will always be to present the facts as they are, even if it takes a while for them to grasp it. Otherwise you run the risk of someone regurgitating a diatribe of information that don't fully understand when asked, and while it makes them sound like they know what they're talking about, when you present another similar problem with different variables, suddenly they're lost and confused again.

It's only when you see their eyes get a little wide, and you know they've truly "gotten it", do you know their level of comprehension has grown.

But here on this forum (or any others), it's different, granted - people want quick explanations, because we're not in class here. But the teacher/mentor side of me won't shove crap at them, because I wouldn't do it any other place.

EDIT: I've stroked my own ego once or twice by the way - I just have a passion for electronics and electrical theory, so I like to talk about it.

 

[3db]

It's no problem dude, I've got thick skin. I agree that a lot of times, people do post ridiculously technical answers to seemingly simple questions, maybe just to stroke their own ego - I don't know. I've been both a student and a teacher on these matters, and I can tell you honestly, that the best approach will always be to present the facts as they are, even if it takes a while for them to grasp it. Otherwise you run the risk of someone regurgitating a diatribe of information that don't fully understand when asked, and while it makes them sound like they know what they're talking about, when you present another similar problem with different variables, suddenly they're lost and confused again.

It's only when you see their eyes get a little wide, and you know they've truly "gotten it", do you know their level of comprehension has grown.

But here on this forum (or any others), it's different, granted - people want quick explanations, because we're not in class here. But the teacher/mentor side of me won't shove crap at them, because I wouldn't do it any other place.

EDIT: I've stroked my own ego once or twice by the way - I just have a passion for electronics and electrical theory, so I like to talk about it.

I took EE as well and I'm not a word smith

 

[TLS Guy]

I took EE as well and I'm not a word smith

We seem to be stiff with electrical engineers round here. I'm going to get run in for practicing without a license!