[hamdani yusuf]

Exceptions to Faraday's law are already known.
https://en.wikipedia.org/wiki/Faraday%27s_law_of_induction#EMF_for_non-thin-wire_circuits

EMF for non-thin-wire circuits
It is tempting to generalize Faraday's law to state: If ∂Σ is any arbitrary closed loop in space whatsoever, then the total time derivative of magnetic flux through Σ equals the EMF around ∂Σ. This statement, however, is not always true and the reason is not just from the obvious reason that EMF is undefined in empty space when no conductor is present. As noted in the previous section, Faraday's law is not guaranteed to work unless the velocity of the abstract curve ∂Σ matches the actual velocity of the material conducting the electricity.[28] The two examples illustrated below show that one often obtains incorrect results when the motion of ∂Σ is divorced from the motion of the material.


Faraday's homopolar generator. The disc rotates with angular rate ω, sweeping the conducting radius circularly in the static magnetic field B (which direction is along the disk surface normal). The magnetic Lorentz force v × B drives a current along the conducting radius to the conducting rim, and from there the circuit completes through the lower brush and the axle supporting the disc. This device generates an EMF and a current, although the shape of the "circuit" is constant and thus the flux through the circuit does not change with time.


A wire (solid red lines) connects to two touching metal plates (silver) to form a circuit. The whole system sits in a uniform magnetic field, normal to the page. If the abstract path ∂Σ follows the primary path of current flow (marked in red), then the magnetic flux through this path changes dramatically as the plates are rotated, yet the EMF is almost zero. After Feynman Lectures on Physics Vol. II page 17-3

[Mitko Gorgiev (OP)]

I have tried to move a wire in front of a magnet, and I can see some current was generated in the wire by the reading of a milliammeter. The current must form a closed circuit to enable reading. A short conductor falling in a magnetic field may generate eddy current which in turn resist its movement, but it still requires a closed loop.
In my experiment, I can only find one bump of current reading when a neodymium magnet is moved pass the milliampmeter's wire which forms a closed circuit. This agrees with Faraday's law that the current is proportional to dB/dt.
With finite speed, there would be no vertical line on the oscilloscope.

Dear Hamdani,
I don't believe in your experimental setups. You have once tried to pervert a very important experiment. Here it is:
https://www.thenakedscientists.com/forum/index.php?topic=78153.msg591478#msg591478

A short conductor falling in a magnetic field may generate eddy current which in turn resist its movement, but it still requires a closed loop.

What short conductor? You refer probably to the figure of mine where the conductor is falling inside the magnetic field from point A to point B. But it is not a short conductor. It can be very long and connected to an oscilloscope. The figure shows a cross-section of the conductor. It is viewed sideways. You have completely misunderstood the setup.

*  *  *
Let me ask you something. Please look at the figure below:

moving conductors.png (3.24 kB . 300x330 - viewed 4747 times)

A conductor is moving from point A to point B with velocity v. This is the first variant.
In the second variant the same conductor is moving from point A1 to point B1 with the same velocity v as in the first variant. In which case the current will be stronger? I claim that in the first case the current will be many, many times stronger. Would you bet with me on this?

*  *  *
Would you try to answer the question I have asked my opponents above? Let us hear your theoretical opinion.

[Bored chemist]

The Bored chemist has solved it, but he is ashamed to tell us the solution, because he loses as usual.

Until you stop messing about and actually answer the question I asked, I don't know what you are talking about.
Consequently, I can't "solve" it.
I'm obviously not ashamed of your inability to answer a question.
I don't have anything to lose here; I'm still trying to find out what you are talking about.

[Mitko Gorgiev (OP)]

The Bored chemist has solved it, but he is ashamed to tell us the solution, because he loses as usual.

Until you stop messing about and actually answer the question I asked, I don't know what you are talking about.
Consequently, I can't "solve" it.
I'm obviously not ashamed of your inability to answer a question.
I don't have anything to lose here; I'm still trying to find out what you are talking about.

I usually answer your questions, but you never answer my questions. It is true that I am the original poster of this thread, but once you have entered the discussion, then I consider that you have to answer also my questions.
Hence, answer my question first and then I will answer your question.
hence

[hamdani yusuf]

What short conductor?

See this video. Skip to 2:50

[hamdani yusuf]

I don't believe in your experimental setups

Why don't you try it yourself? It's not that difficult.

[Bored chemist]

Are you really too dumb to recognise that, until you answer my question (which asks you to clarify your point of view), I can't answer your question because you have  not told me what that question means?

So, stop wasting time and explain what you are talking about.

[Mitko Gorgiev (OP)]

What short conductor?

See this video. Skip to 2:50

You link a video which doesn't have anything to do with the problem we discuss and you avoid to answer my questions.
So, let me remind you:

hamdani.png (8.19 kB . 520x330 - viewed 7606 times)

Question 1 (figure (a)):
In which case the current will be stronger? When the conductor is moving from A to B or when it is moving from A1 to B1?

Question 2 (figure (b)):
What will happen when the conductor is moving from A to C through B? How will the induced current change?

If you answer my questions, I will answer you why I think that the linked video has nothing to do with the subject here and also other unanswered things, if any.

[Bored chemist]

You link a video which doesn't have anything to do with the problem we discuss and you avoid to answer my questions.

Well, I understood the relevance.
Why don't you?

[Mitko Gorgiev (OP)]

You link a video which doesn't have anything to do with the problem we discuss and you avoid to answer my questions.

Well, I understood the relevance.
Why don't you?

Would you answer the questions for Hamdani?

[Bored chemist]

OK, eBay's an odd source to cite but it shows the point nicely. There's a picture here
https://www.ebay.co.uk/itm/Fine-Iron-Filings-Fillings-and-Bar-Magnet-Combo-for-magnetism-experiments-200g-/180833657211
which I think we can agree is a "real" picture- not photoshop or whatever.

Here's a clip from it

field.png (141.61 kB . 407x244 - viewed 3863 times)

And, as you can see the field is not parallel near the end of the magnet.
So, moving a wire in that field will give a rather complicated induced voltage.

That's why I keep asking what sort of field you think you are talking about.
But, because you are not interested in doing science, you don't answer.

[Bored chemist]

Would you answer the questions for Hamdani?

You seem to have forgotten who was asking questions.

What short conductor?

[hamdani yusuf]

Would you answer the questions for Hamdani?

You seem to have forgotten who was asking questions.

What short conductor?

That's exactly why I posted the video of a moving conductor plate around a large magnet.

[hamdani yusuf]

So, let me remind you:

 

Question 1 (figure (a)):
In which case the current will be stronger? When the conductor is moving from A to B or when it is moving from A1 to B1?

Question 2 (figure (b)):
What will happen when the conductor is moving from A to C through B? How will the induced current change?

If you answer my questions, I will answer you why I think that the linked video has nothing to do with the subject here and also other unanswered things, if any.

It depends on the distribution of magnetic flux density in the space cut through by the wire, including the return path to the amperemeter. BC has pointed out that the field is not parallel near the end of the magnet.
The video below shows how the magnetic field is distributed around a permanent magnet.

[Mitko Gorgiev (OP)]

It depends on the distribution of magnetic flux density in the space cut through by the wire, including the return path to the amperemeter. BC has pointed out that the field is not parallel near the end of the magnet.
The video below shows how the magnetic field is distributed around a permanent magnet.

This is not an answer. This is only complicating a very simple question, which means avoiding to answer it. I have already answered one of the questions here:.
https://www.thenakedscientists.com/forum/index.php?topic=78772.msg594433#msg594433

I think that this is a problem of morality. Some people do not want to admit the truth regardless of how strong are the proofs someone brings forward. And it has to do with the moral.
 

[Bored chemist]

Some people do not want to admit the truth regardless of how strong are the proofs someone brings forward.

You have not put forward any proofs, so it is not clear what you are talking about.

[hamdani yusuf]

It depends on the distribution of magnetic flux density in the space cut through by the wire, including the return path to the amperemeter. BC has pointed out that the field is not parallel near the end of the magnet.
The video below shows how the magnetic field is distributed around a permanent magnet.

This is not an answer. This is only complicating a very simple question, which means avoiding to answer it. I have already answered one of the questions here:.
https://www.thenakedscientists.com/forum/index.php?topic=78772.msg594433#msg594433

I think that this is a problem of morality. Some people do not want to admit the truth regardless of how strong are the proofs someone brings forward. And it has to do with the moral.
 

Unexpected results come from false assumptions. One of yours which I can identify is assuming that magnetic field lines around a magnetic pole are parallel, which is demonstrably false by the experiment.
When the magnetic field lines are parallel, and we move the magnet relative to conductor along those lines, we got no electric current, as I have shown in my own experiment.
If you have some idea regarding truth and morality, feel free to join my discussion in a thread about universal morality.

[Mitko Gorgiev (OP)]

It depends on the distribution of magnetic flux density in the space cut through by the wire, including the return path to the amperemeter. BC has pointed out that the field is not parallel near the end of the magnet.
The video below shows how the magnetic field is distributed around a permanent magnet.

This is not an answer. This is only complicating a very simple question, which means avoiding to answer it. I have already answered one of the questions here:.
https://www.thenakedscientists.com/forum/index.php?topic=78772.msg594433#msg594433

I think that this is a problem of morality. Some people do not want to admit the truth regardless of how strong are the proofs someone brings forward. And it has to do with the moral.
 

Unexpected results come from false assumptions. One of yours which I can identify is assuming that magnetic field lines around a magnetic pole are parallel, which is demonstrably false by the experiment.
When the magnetic field lines are parallel, and we move the magnet relative to conductor along those lines, we got no electric current, as I have shown in my own experiment.
If you have some idea regarding truth and morality, feel free to join my discussion in a thread about universal morality.

No, my ideas about morality I will discuss elsewhere, because you are a great disappointment for me.
So, analyze how much you will what is the field around an ORDINARY CYLINDRICAL MAGNET and then answer the questions.

[Bored chemist]

, analyze how much you will what is the field around an ORDINARY CYLINDRICAL MAGNET and then answer the questions.

What you get will be different from what you have drawn
It's easy enough to do the experiment; why not try it?

[Mitko Gorgiev (OP)]

I have uploaded an experiment video on electric generation by moving magnets through a coil.

Let us know if the result agrees with your expectation.

I didn't think about your experiment at that time because I thought it is not very relevant to the discussed issue.
I have watched it again today, replicated it and found the explanation.
I am busy now with another thing, but I hope to write it tomorrow.

Have you perhaps found the explanation in the meantime?