Extended Faraday Disk: How is Energy Conserved?

In summary: The lines radiating out from the black circles show the paths the electrons will follow.In summary, the Faraday disk generates a current, but the current does not flow between the magnets because there is a counter torque.
  • #1
Samson4
245
15
In the diagram, I am focusing on the area in the green circle.
So this is basically 2 Faraday disk with the magnets opposing and concealed in a copper cylinder. Now if we spin the cylinder a current is generated such as the current following the red arrows.

My Confusion: As the current passes between the magnets, a torque is also produced. The force should be in the same direction as the torque that created the current. Seeing as how most of the lines of flux coming from the north face of the magnets are parallel to the cylinder walls and perpendicular to the disks; shouldn't there be a current generated and a torque. How is energy conserved?

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  • #2
You have closed the “purple” magnetic circuit, but not the “red” electron current circuit.
I can see no path for the current to close the loop, so a voltage will be generated without current.
Are you sure you have the correct magnet polarity?
 
  • #3
Baluncore said:
You have closed the “purple” magnetic circuit, but not the “red” electron current circuit.
I can see no path for the current to close the loop, so a voltage will be generated without current.
Are you sure you have the correct magnet polarity?

It would have brushes just like a regular faraday disk. I didn't want to add anymore junk to such a mess of color. A brush would be present on the rods on both sides of the cylinder.
 
  • #4
Any purple flux that passes through a copper disk must also pass back through the copper cylinder.
Will all axial currents not cancel to zero?
The copper is never subjected to a changing magnetic flux since the field and copper are axially symmetrical.
 
  • #5
There is a counter torque, because the electrons that form the current feel a Lorentz force, and then somehow that force is transmitted to the whole disk. Maybe the force is transmitted by resistance. Does Faraday disk work if the disk is superconducting?
 
  • #6
Baluncore said:
Any purple flux that passes through a copper disk must also pass back through the copper cylinder.
Will all axial currents not cancel to zero?
The copper is never subjected to a changing magnetic flux since the field and copper are axially symmetrical.

So far that's the only solution I can think of. So there should be no current flow from 1 rod to the other.
I don't understand what you mean with the second part of your post.
 
  • #7
jartsa said:
There is a counter torque, because the electrons that form the current feel a Lorentz force, and then somehow that force is transmitted to the whole disk. Maybe the force is transmitted by resistance. Does Faraday disk work if the disk is superconducting?

If torque is generated it does not oppose the applied torque.
 
  • #8
On a related note, which path do you think the electrons will follow in this image? All the blocks are the same conductive material. The black circles are connections at a dc power source.
path.png
 

1. How does the Extended Faraday Disk work?

The Extended Faraday Disk is a device that converts kinetic energy into electrical energy through the principle of electromagnetic induction. It consists of a spinning disk made of a conductive material, such as copper or aluminum, and a magnetic field produced by a permanent magnet or electromagnet. This creates a potential difference between the center and outer edge of the disk, generating an electric current.

2. What is the purpose of the Extended Faraday Disk?

The Extended Faraday Disk is used to demonstrate the conservation of energy, as it converts one form of energy (kinetic) into another form (electrical). It is also used in power generation, as it can produce a steady flow of electricity when connected to a load.

3. How is energy conserved in the Extended Faraday Disk?

Energy is conserved in the Extended Faraday Disk through the principle of conservation of energy, which states that energy cannot be created or destroyed, only transferred from one form to another. In this case, the kinetic energy of the spinning disk is converted into electrical energy.

4. What factors affect the amount of energy produced by the Extended Faraday Disk?

The amount of energy produced by the Extended Faraday Disk depends on several factors, such as the speed of the disk, the strength of the magnetic field, the size and material of the disk, and the resistance of the circuit connected to the disk.

5. Can the Extended Faraday Disk be used to generate large amounts of electricity?

Yes, the Extended Faraday Disk can be used to generate electricity, but it may not be practical for large-scale power generation due to its limited efficiency. Other methods, such as using turbines in power plants, are more efficient for producing large amounts of electricity.

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