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Posted

Yes ,he never has a typo does he.  Stop sending advertisements to your gapminder website nobody

wants to read that propaganda.  This is not a dictionary its a blog.

Posted
10 minutes ago, Doug Jones said:

Stop sending advertisements to your gapminder website nobody wants to read that propaganda

It is not my website. It is not propaganda. It is an educational resource. People should be interested. 

As 2 of your first 3 posts appear to be spam...

12 minutes ago, Doug Jones said:

This is not a dictionary its a blog.

This is neither

Posted
14 hours ago, Doug Jones said:

Yes ,he never has a typo does he.  Stop sending advertisements to your gapminder website nobody

wants to read that propaganda.  This is not a dictionary its a blog.

!

Moderator Note

I don't know what your problem is with someone having a link in their signature, but it's within the rules, and chastising someone about it is not. Please cease with such off-topic commentary.

 
  • 3 weeks later...
Posted

I have conducted yet another experiment with rotating magnetic field and stationary water and salt based ionic cell with stainless steel electrodes and again it has failed to produce expected EMF therefor I now conclude that  Lorentz force and law must be defective and or false ...

This inconsistency was also found by Tony Rothman and published in his article with a link here:  https://scholarship.haverford.edu/cgi/viewcontent.cgi?referer=https://www.google.com/&httpsredir=1&article=1062&context=astronomy_facpubs

IonicCell.jpg

  • 1 month later...
Posted
On 11/09/2018 at 11:32 AM, icester said:

Here is my setup with rotating magnet a stationary  wire connected to 1 mega ohm scope probe at 50 mV per division scale and there is 0 DC offset at maximum rpm of 10000 or less...

 

IMG_20180911_091119.jpg

I can't see why you would expect any voltage to be generated. As far as I can see, you have a stationary wire in a static magnetic field.

On 06/11/2018 at 9:21 AM, icester said:

This inconsistency was also found by Tony Rothman and published in his article with a link here: 

I can't see any connection between that paper and your experiment. Can you explain?

Posted (edited)
3 minutes ago, Strange said:

I can't see why you would expect any voltage to be generated. As far as I can see, you have a stationary wire in a static magnetic field.

Magnet is rotating at 10000 rpm... Rotating wire in stationary magnet  is the same... But Lorentz believed in aether an absolute motion...

 

Edited by icester
Posted
1 minute ago, icester said:

Magnet is rotating at 10000 rpm...

What is the orientation of the magnetisation of that disk? I am assuming that one face of the disk is the North pole and the other face is the South pole. In which case, the rotation will not have any effect on the magnetic field.

 

Posted
8 minutes ago, Strange said:

What is the orientation of the magnetisation of that disk? I am assuming that one face of the disk is the North pole and the other face is the South pole. In which case, the rotation will not have any effect on the magnetic field.

 

Yes, exactly but MIT physics reference  (10.2 Motional EMF) claims it generates EMF:  http://web.mit.edu/viz/EM/visualizations/coursenotes/modules/guide10.pdf

 

Posted
Just now, Strange said:

You'll have to be more specific. I skimmed through a few pages of that but couldn't see anything that corresponds to your setup. Can you specify a page or figure number?

Page 10-7 

 

Posted
Just now, icester said:

Page 10-7 

 

That says: "Consider a conducting bar of length l moving through a uniform magnetic field..."

So if you move the wire, you will get a voltage. But your spinning disk does not (as far as I can see) generate a changing magnetic field.

Can you explain how it is magnetised and why you think it will generate a changing magnetic field?

Posted
Just now, Strange said:

That says: "Consider a conducting bar of length l moving through a uniform magnetic field..."

So if you move the wire, you will get a voltage. But your spinning disk does not (as far as I can see) generate a changing magnetic field.

Can you explain how it is magnetised and why you think it will generate a changing magnetic field?

It is the same, relative motion between field and wire. I've done the rotating wire in stationary magnetic field and there was no EMF...

One could simply measure the voltage between the ends of a wire moving in Earth magnetic field but it does not work, but classroom physics says it does...

Just now, icester said:

It is the same, relative motion between field and wire. I've done the rotating wire in stationary magnetic field and there was no EMF...

One could simply measure the voltage between the ends of a wire moving in Earth magnetic field but it does not work, but classroom physics says it does...

There is no single experiment to confirm what MIT claims...

Posted
3 minutes ago, icester said:

It is the same, relative motion between field and wire. I've done the rotating wire in stationary magnetic field and there was no EMF...

But I don't believe you have a moving magnetic field.

Can you explain how the disk is magnetised (ie in which direction; where the N and S poles are) and why you think it will generate a changing magnetic field?

4 minutes ago, icester said:

One could simply measure the voltage between the ends of a wire moving in Earth magnetic field but it does not work, but classroom physics says it does..

Calculate the voltage generated in this way and tell me if your measuring instrument is able to measure it.

5 minutes ago, icester said:

There is no single experiment to confirm what MIT claims...

Uhm. All of Faraday's experiments. Every similar experiment done at school. Every motor or generator....

Posted (edited)
16 minutes ago, Strange said:

But I don't believe you have a moving magnetic field.

Can you explain how the disk is magnetised (ie in which direction; where the N and S poles are) and why you think it will generate a changing magnetic field?

Calculate the voltage generated in this way and tell me if your measuring instrument is able to measure it.

Uhm. All of Faraday's experiments. Every similar experiment done at school. Every motor or generator....

You are confusing it with induction, there is no induction when conductor moves with constant velocity in uniform magnetic field just like my experiment shows... I can make the magnet wobble slightly and it will generated sinusoidal AC EMF...

7 minutes ago, icester said:

You are confusing it with induction, there is no induction when conductor moves with constant velocity in uniform magnetic field just like my experiment shows... I can make the magnet wobble slightly and it will generated sinusoidal AC EMF...

And there is no changing magnetic field in rotating magnet because it rotates around it's axis of symmetry...

Edited by icester
Posted
11 minutes ago, icester said:

You are confusing it with induction, there is no induction when conductor moves with constant velocity in uniform magnetic field just like my experiment shows...

You are not moving the conductor. 

12 minutes ago, icester said:

I can make the magnet wobble slightly and it will generated sinusoidal AC EMF...

Yes, because then you have s changing magnetic field. 

13 minutes ago, icester said:

And there is no changing magnetic field in rotating magnet because it rotates around it's axis of symmetry...

Exactly. No changing magnetic field so no voltage. 

 

Posted (edited)
38 minutes ago, Strange said:

 No, Faraday homopolar generator works with brushing, if you read my post carefully you will find a link to brush less homopolar generator patent which does not work... Anyway here is 100 year old example on  page 480 claiming that wire moving in constant uniform magnetic field generates EMF:

A College Text-Book of Physics_ 2nd Ed_ Arthur L Kimball_ 1917

The pdf is too big to attach it here but I can email it to you if you want it...

 

 

Edited by icester
Posted
5 hours ago, icester said:

Anyway here is 100 year old example on  page 480 claiming that wire moving in constant uniform magnetic field generates EMF:

Are you moving the wire? I thought it was stationary?

Posted
1 hour ago, icester said:

It does not matter as long as there is relative motion... No absolute motion can exist or can it?

But I don't believe you have a moving magnetic field.

Can you explain how the disk is magnetised (ie in which direction; where the N and S poles are) and why you think it will generate a changing magnetic field?

Posted
19 minutes ago, Strange said:

But I don't believe you have a moving magnetic field.

Can you explain how the disk is magnetised (ie in which direction; where the N and S poles are) and why you think it will generate a changing magnetic field?

Rotating yes, but it does not necessary means changing... Cutting magnetic filed lines but each line has  the same intensity and direction thus comply with definition of uniform magnetic field... So,  as you noted, there is no changing magnetic field... In reality there are no flux lines but only a gradient with axial symmetry...

Posted
10 minutes ago, icester said:

So,  as you noted, there is no changing magnetic field...

Therefore no voltage generated. 

What is the point of this thread? You get exactly the results expected, and yet you seem confused by it. 

Posted
1 hour ago, Strange said:

Therefore no voltage generated. 

What is the point of this thread? You get exactly the results expected, and yet you seem confused by it. 

If you read the thread carefully you will find out that Lorentz claimed otherwise. You do get voltage proportional to the velocity of charge particle moving in uniform magnetic field... There is even online calculator where the apparent Motional EMF can be calculated: http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/genwir3.html#c1

Posted
17 minutes ago, icester said:

If you read the thread carefully you will find out that Lorentz claimed otherwise.

Where does it say that a static wire in a static magnetic field will generate a voltage?

18 minutes ago, icester said:

You do get voltage proportional to the velocity of charge particle moving in uniform magnetic field...

But that is not what you have. You have a static wire. No moving charged particles. No moving magnetic field.

You have a uniform, static, unchanging, non-varying magnetic field.

You have a static, non-moving wire in that uniform, static, unchanging, non-varying magnetic field.

Theory says you will get NO voltage. What does your experiment show? NO VOLTAGE.

What is wrong with that?

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