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Mitko Gorgiev

Faraday's law of induction is not true

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One of the fundamental laws of electromagnetism is the “Faraday's law of induction”. This law states that the induced EMF in a wire loop is equal to the rate of change of the magnetic flux enclosed with the loop, or E=dΦ/dt (the minus sign before “dΦ/dt” is left out because it is not important for our discussion). In the textbooks is often given an example of a loop in the shape of a rectangle which rotates in a magnetic field (figure below).

image.png.a3a878a5cb0d0d9c256e8ddb45e493ab.png

What is meant by “the rate of change of the magnetic flux enclosed with the loop”?
To explain this, we will make a comparison. If we hold a ring in front of our eyes as if we want to see through it, then it has a shape of a circle. If we turn it 90°, we only see a line. In every other intermediate position of the ring, we see an ellipse. In the first position, the ring has the maximum area in front of our eyes; in the second, the minimum, i.e., zero. If the ring starts to rotate about its axis starting from the second position (0) and has turned 180°, then the area we see in the course of this rotation can be represented with a sine curve of half a period.

Similarly, when the wire loop is in the vertical position (according to the image above), then the magnetic flux is zero, and when the wire loop is in the horizontal position, then the flux is maximal. This flux changes according to a sine function, too. So, when the flux is maximal, then the rate of its change is minimal, more precisely, zero, because the slope of the sine curve in this point is zero. But when the flux is minimal, then the rate of its change is maximal, because the slope of the curve in this point is maximal.

So, from the Faraday's law of induction it follows that when the wire loop is in vertical position, then the induced current in the loop is maximal; and when it is in horizontal position, then the induced current in the loop is zero (graph below).

image.png.2e969e0c62c6916572496ac76a50077a.png

If we connect the ends of the wire loop to an oscilloscope, would we really get this curve?!!

Let’s consider the following experiment. From a lacquered copper wire we cut off twenty to thirty pieces of about 10 cm. From them we form a bundle of parallel wires and connect the two ends with one more wire each. The other ends of these two wires are connected to a sensitive analog ammeter. We hold the bundle horizontally and move quickly a strong and broad magnet downwards on its left side. The pointer of the instrument will make a deflection to one side. If we now move the magnet quickly downwards on the right side of the bundle, the instrument will make a deflection to the opposite side. The magnetic flux that we have produced in the wire is now in the opposite direction to the one in the first case, which is why the deflection is in the opposite direction. The motion of the magnet produces current even if we only approach it to the bundle from one side without lowering it below the bundle. In this case the current is somewhat weaker. But if we now move the magnet down to the middle of the bundle, the instrument won’t show any current, because the left and the right halve of the magnet act on opposite sides of the bundle, canceling each other out.
We can do the experiment with only a single wire instead of a bundle, as long as we have a very strong magnet and a very sensitive ammeter.
You can imagine that inside this wire there is a propeller or there are many propellers in a row. When you turn a propeller manually from the left side, then it is turning in one direction and it is blowing on one side (plus), but it is suctioning on the other side (minus). When you turn the propeller from the right side, then it is turning in the contrary direction and the air current is in the opposite direction.
But we cannot turn the propeller from above. Exactly the same picture we have with the magnet and the wire.

image.png.e81859bceda0c98c8a6a60c8f583f4ed.png

After we have lowered the magnet down and have produced a current in one direction, then we can move it back upward. In that case we produce a current in the contrary direction, just as we will produce an air-current in the contrary direction if we turn the propeller(s) from down up.

Whether the magnet is moving toward/away from the wire, or the wire is moving toward/away from the magnet, there is no difference. Therefore, let us consider the following experiments.
A straight conductor is moving vertically exactly toward the middle of a magnet. No current is induced in this conductor (figure a below).
In the second variant (figure b) the conductor is shifted 1 millimeter to the right and is moving again vertically toward the magnet. A current is induced in it which flows away from us.
In the third variant (figure c) the conductor is shifted 1 mm to the left and is moving vertically toward the magnet again. A current is induced in it which flows toward us.

image.png.9d9b141047399219758578a86129e5fc.png

Consider now this experiment: a straight conductor is moving vertically exactly in the middle between two identical magnets [ figure (a) below ]:

image.png.e4cd96dc5b4c931144fa3f95d7fd304f.png

No current is induced in this conductor.
In the figure (b) the conductor is shifted 1 millimeter to the right and is moving again vertically from the lower to the upper magnet. A current is induced in this conductor. But during its movement upwards, the induced current changes the direction. To the dashed line, which is exactly in the middle between the magnets, the induced current flows toward us. When the conductor is exactly in the middle, the current drops to zero. Then, above the dashed line, begins a current flow in opposite direction.
In the figure (c) the conductor is shifted 1 millimeter to the left and is moving again vertically from the lower to the upper magnet. A current is induced in it, but here the reverse happens with respect to that of the figure (b).

Why is this happening? Please look at the drawing below (figure a):

image.png.bb55b177dcfe858a5d4a9307a39ed5d0.png

The magnetic field of the magnet is weaker at a greater distance from the magnet’s pole. At a greater distance than d, we could say that the strength of the magnetic field is practically zero. The weakening of the strength is symbolically represented by the different shades of gray (figure a).

The weakening is also symbolically represented by the red and the blue triangle in the figure (b). If the two identical magnets are brought at the distance ‘d’ (or lesser than ‘d’) without allowing them to come together, then in the interspace between them there is a homogeneous magnetic field because the two fields complement each other. This means that the strength of the magnetic field is the same in every point of the interspace (figure c).

The magnetic field is homogeneous in terms of strength, but it is not homogeneous in terms of polarity. The Plus and the Minus retain their character just as before the bringing of the magnets close to each other. (I call the pole of a compass, which points North, the Plus pole. I will post soon a topic considering this question). 

Please look at the figures below:

image.png.86cd7c0530378c8314d2761af9f43449.png

Here are presented all the eight possible variations of a conductor moving toward and away from a magnet. Consider the first (a) and the last (h) variation. These two variations were unified in a single experiment in the second-to-last figure above (figure b). But what happened there? The current induced in the conductor dropped to zero exactly in the middle between the magnets. How so? Because the Plus and Minus are of the same strength in that point. Therefore they cancel each other out regarding the electromagnetic induction.

Please look now at the figure below.

image.png.623560986dcbfdc2671631d2a6a3c7cc.png

A straight conductor is rotating uniformly counter-clockwise in a homogeneous magnetic field according to the figure above. The rear end of the conductor (that which is farther away from us) is connected to the positive terminal of an oscilloscope, the front end to the negative. What will the graph of the induced current (/voltage) look like?

Please look at the picture below:

image.png.c3aa136d3f64740ce5a6ea452db8153c.png

There are two crossed lines in it, which I call “dead lines”. Whenever the conductor moves through one of these lines, there is no current induced in it. Therefore I have named them “dead lines”. But in reality these dead lines are dead planes. The horizontal plane I call the main middle plane.

Which plane is represented by the vertical line? It can be any vertical plane which goes through the central point between the magnets (that is, the cross point in the diagram above). But which one out of the infinite number of them? That depends on the direction of the conductor. Let’s say that the rotating conductor is positioned exactly in the North-South direction. In that case the vertical plane is also in that direction.

So, when the conductor is rotating in a homogeneous magnetic field as in the figure above, the induced current will be zero in the four points marked with the Roman numbers (graph below).

image.png.17f6252a8d35a08db8753c6b9531946c.png

When a rectangular loop is rotating in a homogeneous magnetic field, then we have in fact only a second identical conductor which rotates diametrally to the first, because only these two sides of the loop play a role in the induction of the current (marked with “L” in the figure below). Since the current in the second conductor has a contrary direction, the induced current in the loop will be twice as strong (recall that it is a loop.) The graph above is valid also for this loop, only we have to draw the waveform twice as high.

image.png.a3a878a5cb0d0d9c256e8ddb45e493ab.png

So, the Faraday’s law of induction is not true because it predicts a wrong result. I believe (and that is not without grounds) that Michael Faraday has never defined this law. He was a great experimentalist and he would have made many experimental trials before definitely defining something.
I rather believe that this law has come among the people through the third of the Maxwell’s equations and somebody has called it so in honor of the great Faraday.
You may ask yourself: Is that equation really true?

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I seem to remember that, when your last thread on this topic was closed, to not bring this up again.

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I think you know which one I meant:

In both cases you are essentially asserting that Maxwell’s equations are not valid, so this is just a repeat of the same thing. 

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4 hours ago, Markus Hanke said:

In both cases you are essentially asserting that Maxwell’s equations are not valid, so this is just a repeat of the same thing. 

Where am I asserting in the thread you have linked that the Maxwell's equations are not valid?

More generally, what has that thread to do with this one?

Moreover, do you have some objections against the things said in this thread?

Otherwise, I would consider your replies as trolling.

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46 minutes ago, Mitko Gorgiev said:

Where am I asserting in the thread you have linked that the Maxwell's equations are not valid?

Maybe the first sentences?

Quote

Electric current is an immaterial swirling wind through the electrical conductor. The immaterial magnetic wind through it is also spiral-shaped (i.e., it is not perpendicular to the conductor as the contemporary physics asserts). 

The above, taken from the linked thread, implies as far as I can tell that Maxwell is not valid.

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14 hours ago, Mitko Gorgiev said:

The weakening of the strength is symbolically represented by the different shades of gray (figure a).

It isn't represented very well.

A set of semi-circles would be a better picture than a set of bars.

This has been pointed out to you before.
You persistently troll your unrealistic view.

14 hours ago, Mitko Gorgiev said:

This means that the strength of the magnetic field is the same in every point of the interspace (figure c).

 

Again, that's simply not true. It it was, the designers of NMR machines would have a much easier time.

14 hours ago, Mitko Gorgiev said:

The magnetic field is homogeneous in terms of strength, but it is not homogeneous in terms of polarity.

If you think about that, you will realise it is nonsense

It can't go from + to - without going through zero And if it is zero in some places, but not others, it is not homogeneous.

And, because you don't have a sensible model of what the field is like, your ideas about what would happen if you moved a conductor through that field are also wrong.


 

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16 hours ago, Mitko Gorgiev said:

 

So, from the Faraday's law of induction it follows that when the wire loop is in vertical position, then the induced current in the loop is maximal; and when it is in horizontal position, then the induced current in the loop is zero (graph below).

image.png.2e969e0c62c6916572496ac76a50077a.png

If we connect the ends of the wire loop to an oscilloscope, would we really get this curve?!!

Good question. Why don't you do this experiment, instead of mucking about with qualitative descriptions?

(I've done a similar one - spun a magnet inside of a coil, and got oscillatory behavior. So your objection has to be more specific in detailing what's wrong with Faraday's law)

 

Quote

Please look at the picture below:

image.png.c3aa136d3f64740ce5a6ea452db8153c.png

There are two crossed lines in it, which I call “dead lines”. Whenever the conductor moves through one of these lines, there is no current induced in it. Therefore I have named them “dead lines”. But in reality these dead lines are dead planes. The horizontal plane I call the main middle plane.

Why is the current a maximum when the wire loop is in the vertical position in your first example, but there is no current induced in that configuration here?

 

 

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3 hours ago, swansont said:

Why is the current a maximum when the wire loop is in the vertical position in your first example, but there is no current induced in that configuration here?

The first example including the sine curve is what the induced current would be according to the Faraday's law. It predicts a sine waveform whose maximum should be when the loop is in the vertical position (according to the first image of the rotating loop in my OP). 
I claim that in the vertical position of the loop the current will drop to zero. The current will also drop to zero when the loop is in the horizontal position. Therefore, we will not get a sine curve on the oscilloscope, but a curve as I draw it in my OP:image.png.17f6252a8d35a08db8753c6b9531946c.png
The maximum(s) will be actually in the moments when the loop is in the position of 45 degrees.

This is quite enough to disprove the Faraday's law.

Quote

Good question. Why don't you do this experiment, instead of mucking about with qualitative descriptions?

I don't have to do that experiment. I can conclude what the waveform of the induced current will be on the basis of much simpler experiments. 
If someone has the means to carry it out, let him do it. I bet that I am right.
Would you bet that I am not?

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So, what does this mean ?
My electric drill no longer works ?

People are 'delusional' when they argue against reality.
( not to worry, there's medication for that )

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33 minutes ago, Mitko Gorgiev said:

Therefore, we will not get a sine curve on the oscilloscope, but a curve as I draw it in my OP:image.png.17f6252a8d35a08db8753c6b9531946c.png
The maximum(s) will be actually in the moments when the loop is in the position of 45 degrees.

 

How come identical situation (orientation, angular velocity,...) of the magnets and the rotating circuit gives rise to opposite effects in I-II and in III-IV?

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3 hours ago, Mitko Gorgiev said:

This is quite enough to disprove the Faraday's law.

No, it’s not. It shows you don’t understand electromagnetism 

Quote

I don't have to do that experiment.

Experiment is the only way you can falsify a theory

 

Here’s the experiment I did

http://blogs.scienceforums.net/swansont/archives/9120

Spinning magnet dropped through a coil. 

B0803B3E-0426-4C44-9980-ED52BF4F810F.jpeg

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3 hours ago, Mitko Gorgiev said:

Would you bet that I am not?

I would bet that you are wrong, and so would the entire electricity generating industry.

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2 hours ago, joigus said:

How come identical situation (orientation, angular velocity,...) of the magnets and the rotating circuit gives rise to opposite effects in I-II and in III-IV?

Look please at the figure below:

image.png.b466724103b9bffb2dc3e9d682dfe79e.png

The red and the blue circles are cross sections of the two relevant sides of the rectangular loop. 
The two ends of the loop are connected to two slip rings. One slip ring is connected to the Plus-terminal of an oscilloscope; the other slip ring is connected to the Minus-terminal
Let's say we have colored the two relevant sides of the loop - one in red colorthe other in blue color.
In the figure (b) the loop has rotated 180 degrees with respect to its position in the figure (a).
Can you guess what I am going to say next?

51 minutes ago, John Cuthber said:

I would bet that you are wrong, and so would the entire electricity generating industry.

How much would you bet? I will bet as much as you say.

 

1 hour ago, swansont said:

Here’s the experiment I did

http://blogs.scienceforums.net/swansont/archives/9120

Spinning magnet dropped through a coil. 

Dropping a magnet through a coil is completely different setup from a loop which rotates in a magnetic field.

 

1 hour ago, swansont said:

No, it’s not. It shows you don’t understand electromagnetism 

The time will tell. Just sit back and relax.

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22 minutes ago, Mitko Gorgiev said:

Dropping a magnet through a coil is completely different setup from a loop which rotates in a magnetic field.

 

A rotating magnet. What’s the difference if you rotate the coil or you rotate the magnet? The change in flux is the same.

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16 minutes ago, Mitko Gorgiev said:

Can you guess what I am going to say next?

You don't make any sense, how can I guess what you're going to say next?

You are clueless about electromagnetism. That's all I can say. No matter how many colours you use in your drawings.

As to the mathematics (no wonder it's absent in your explanation), I can't even begin to tell you how inconsistent your idea is with everything we know.

And finally, what you're saying is falsified by experiments every which way.

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25 minutes ago, joigus said:

You don't make any sense, how can I guess what you're going to say next?

You are clueless about electromagnetism. That's all I can say. No matter how many colours you use in your drawings.

Since you cannot guess, I would say that the one who is clueless about electromagnetism is you.
I will explain it to you tomorrow and answer to the other replies.
It is pretty late in Macedonia. I have to go to sleep now.

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9 minutes ago, Mitko Gorgiev said:

Since you cannot guess, I would say that the one who is clueless about electromagnetism is you.
I will explain it to you tomorrow and answer to the other replies.
It is pretty late in Macedonia. I have to go to sleep now.

Maybe I missed something all those years of measuring with ammeters and voltimeters, and oscilloscopes. Differentiating the equations to get the error formulas, actually doing the experiment, crunching the numbers for the analysis of errors, and reporting the results.

I cannot guess the pointless next step of your "idea" because it's impossible to guess what's going to come next after a babbling nonsense like yours.

Last time I measured it in a laboratory of electricity, Faraday's law was correct to within the error bars. Even though I was a terrible experimentalist, not even I was able to get it wrong.

And then studying the theory and learning how to solve the equations forwards and backwards... Faraday's law is actually necessary for the Lorentz symmetry of the theory. Angular momentum in particular would not be well defined or conserved either. The symmetries are too tight. You need it for charge conservation too.

The homogeneous terms of the Maxwell equations are actually forced upon you from a pure geometric identity (Bianchi identity) or from first principles of mechanics, after you arrange the E and B fields in their proper Lorentz-invariant form (Feynman's proof of Maxwell's equations.) But first you must understand also what a gauge theory is, something you cannot even begin to fathom.

Moronic pseudo-science. That's what your sorry excuse for an idea is.

Sleep well.

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10 hours ago, joigus said:

 Last time I measured it in a laboratory of electricity, Faraday's law was correct to within the error bars. Even though I was a terrible experimentalist, not even I was able to get it wrong.

I recall when I was a teaching assistant there was a lab on Faraday's law. You had a coil with some number of turns, and you flipped it and looked at the induced current in a circuit. Students used it to deduce the earth's magnetic field. And it worked reasonably well.

One fun part of this was that students on one corner of the room got a different answer because there was an NMR lab one floor up, and when that magnet was on, it was strong enough to affect the field in that corner of the room. So they got a number noticeably larger than students at the other side of the room.

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3 minutes ago, swansont said:

One fun part of this was that students on one corner of the room got a different answer because there was an NMR lab one floor up, and when that magnet was on, it was strong enough to affect the field in that corner of the room. So they got a number noticeably larger than students at the other side of the room.

Now that this thread has reached the wonderful anecdotal climax, many thanks I love it +1, surely the thread can be closed as a repeat of earlier nonsense.

 

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10 hours ago, joigus said:

Maybe I missed something all those years of measuring with ammeters and voltimeters, and oscilloscopes.

Yes, you have missed many things because you cannot solve a very simple task.

I had to add only these sentences in my last post:

In the red cross section of the figure (a) the current flows away from us and then enters the Plus-input of the oscilloscope (represented with the Plus-sign in the figures a and b). Therefore we get a positive voltage on the screen.
In the
blue cross section of the figure (b) the current flows also away from us and then enters the Minus-input of the oscilloscope (represented with the Minus-sign in the figures a and b). Therefore we get a negative voltage on the screen.

image.png.b466724103b9bffb2dc3e9d682dfe79e.png

WOW, what a number of attacks without any real argument against the things said in my OP.
You all really got upset.
Let's bet if you are so sure. How much would you bet?

“All truth passes through three stages. First, it is ridiculed. Second, it is violently opposed. Third, it is accepted as being self-evident.” Arthur Schopenhauer

 

Edited by Mitko Gorgiev

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1 hour ago, swansont said:

I recall when I was a teaching assistant there was a lab on Faraday's law. You had a coil with some number of turns, and you flipped it and looked at the induced current in a circuit. Students used it to deduce the earth's magnetic field. And it worked reasonably well.

One fun part of this was that students on one corner of the room got a different answer because there was an NMR lab one floor up, and when that magnet was on, it was strong enough to affect the field in that corner of the room. So they got a number noticeably larger than students at the other side of the room.

Nice anecdote. Thanks for sharing.

As I said, I was really clumsy in the laboratory. But one thing I did well: I never crossed out any data reading because they gave a freak result. They all made it to my error bars.

They were probably just fluctuations, some due to my sloppiness.

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1 hour ago, Mitko Gorgiev said:

“All truth passes through three stages. First, it is ridiculed. Second, it is violently opposed. Third, it is accepted as being self-evident.” Arthur Schopenhauer

[T]he fact that some geniuses were laughed at does not imply that all who are laughed at are geniuses. They laughed at Columbus, they laughed at Fulton, they laughed at the Wright brothers. But they also laughed at Bozo the Clown.  
— Carl Sagan

Alas, to wear the mantle of Galileo it is not enough that you be persecuted by an unkind establishment, you must also be right.
— Robert Park

!

Moderator Note

Showing that you are right requires experimental confirmation. It also requires that one be able to try and falsify your idea. And I have provided an experimental result that falsifies your idea (it is completely unsurprising that you dismissed this without justification and have not pursued it further. Instead, you repeat your assertions). Plus descriptions of other experiments that confirm Faraday's law. Others have pointed out that motors and generators run in accordance with Faraday's law, and would not work if things were as you claimed. 

So what I mean here is that quoting Schopenhauer and invoking the fallacious "if you are resisting I must be right" stance implies you have no evidence to present. You were given the opportunity, and you chose not to. There's no point in wasting more of anyone's time.

Don't bring this topic up again.

 

 

 

 

 

 

 

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