MrAl,
[In reference to asking real life people in various locations in the world if they know what happened to a battery that was 'energized']
Yes, I will. However, I don't get a chance to do that activity very much. I'll keep it in mind, however.
Ratch
ljcox,
Thank you for pointing out where you think I have been wrong. The links I provided to you seem to say that charge flows across vacuum dielectrics and other strange stuff. They are remiss in not telling you that those are fictious artificial concepts devised by Maxwell to explain some contradictions and paradoxes in the application of his equations. Displacement current does not transport real charge. That's what I told you. In essence, I said that there are no charge carriers in a vacuum, therefore it is not a conduction current - it is a displacement current. Look at the link below and find "displacement current". Then read the last sentence.
New Scientist - Google Books
That kind of explanation can be found elsewhere, too. Displacement Current Does Not Exist
Since you have been told a lot of things by several people, so I thought you would profit by a link to a MIT course that addresses that topic. Enjoy the explanation by a professor who has forgotten more about electromagnetics than we will ever learn.
YouTube - Displacement Current Theory
Ratch
Did you look at his Displacement Current Example 2?
He concludes that the conduction current I is equal to the Displacement current Id.
if you read my whole post you would see that i had stated that charge passes through an inductor and creates a field and that charge actually gets through and doesnt have to change just because it created a field. I thought that would carry over to the capacitor for the counter point.
Thus the conclusion is that the current density due to dE/dt is not a real current, it's just something happening that happens to work out to the same units as current.
It is a long time since I studied antenna theory so I don't know the context of his remark. Besides, it is beside the point.ljcox,
Yes, it is there in the mathematics. I played the lecture again and listened carefully. I did not hear him say that the displacement current was a conduction current. I did not say that he did! He did say that the displacement current was caused by a change in the electric flux density with respect to time, had units of current, and was very small. Wrong, he showed that Id = Ic where Ic is the conduction current in the wire. As far as I can see, it is a mathematical artifice used to make Maxwell's equations come out correct. That is similar to the conventional current method, where we assume all the charge carriers are positive, and calculate the currents/voltage mathematically that way, even though we know very well that the real physical charges are not positive. Have you ever heard of protons, + ions, positrons, etc.? Other references I have read do distinguish between "conduction current" and "displacement current". They even mention different kinds of displacement current.
Now, you have heard of the the law called the Convervation of Charges, right? It basically says that all charge has to come from somewhere, and cannot just disappear. You and others think current can exist without any physical charge flow in a vacuum or a tight dielectric. No, that shows your misunderstanding of Id. Id is not a flow of charge carriers. Others accuse me of changing the definition of meanings, but that belief is a real mind snapper. Current is charge flow, and to have a physical current you need a physical charge to move. That is your basic assumption. I don't agree with that assumption. You should also notice in the second link that the author avers that the displacement current theory does not work well in antenna design.
One final thought. In your studies you have come across Kirchoff's Law, Gauss's Law, Lenz's Law, Newton's Law, Ampere's Law, etc. I have never heard of displacement current being referred to as a law. It is referred to as a theory, or just "displacement current". Look at the title of the lecture.
By that reasoning, then theories such as Einstein's Theory of Relativity are not factual.
Ratch
We are talking about displacment current through a capacitor.
It has:-
1. the dimensions of current
2. has a magnetic field
3. is equal to the conduction current in the wire.
He showed that Ic = 1.2 Amp & Id = 1.2 Amp.ljcox,
I would hope so.
As does all current
No, the prof said it was much smaller than the conduction current, and not caused by the same thing. Did you read my link to Al's reply about it being a "fictious" entity. I did not come up with that, the physics website did. Wrong!
Ratch
It is referred to as a theory, or just "displacement current". Look at the title of the lecture.
By that reasoning, then theories such as Einstein's Theory of Relativity are not factual.
...
I believe I said that just because current can be measured on both sides of the capacitor was not proof that charge passes through the capacitor. If it did, the charge would not accumulate and it would not do what a capacitor does, store energy. Why didn't you discuss this earlier?
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