Exploring the Mysterious Attraction Between Permanent & Superconducting Magnets

In summary, it is possible for a permanent magnet to be attracted to a cooled superconductor magnet, but why does it not attract the permanent magnet to the point that their surfaces come in direct physical contact similar to the attraction that causes two permanent magnets join together when their opposing poles are placed in sufficient proximity? There are many videos showing the permanent magnet levitating above the superconducting magnet and requiring a certain amount of force to be pulled away, but when the permanent magnet is pressed against the superconducting magnet, it bounces back to a specified height like a spring. It is not clear why this is happening.
  • #1
Bararontok
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It is possible for a permanent magnet to be attracted to a cooled superconductor magnet as shown in many experiments, but why does it not attract the permanent magnet to the point that their surfaces come in direct physical contact similar to the attraction that causes two permanent magnets join together when their opposing poles are placed in sufficient proximity? There are many videos showing the permanent magnet levitating above the superconducting magnet and requiring a certain amount of force to be pulled away, but when the permanent magnet is pressed against the superconducting magnet, it bounces back to a specified height like a spring. Why is this happening?

Another interesting question is how the magnetic field of the superconductor remains stable even when the external magnetic field of the permanent magnet exerts a torque that breaks the alignment of the anti-parallel electron pairs that lose their dipole alignment easily because anti-parallel arrangements have difficulty generating the persistent mass magnetic field in the first place.
 
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  • #2


Bararontok said:
There are many videos showing the permanent magnet levitating above the superconducting magnet and requiring a certain amount of force to be pulled away, but when the permanent magnet is pressed against the superconducting magnet, it bounces back to a specified height like a spring. Why is this happening?
Those videos shows permanent magnet levitating over a surface of superconductor, not over superconducting magnet. Superconductors are ideal diamagnetics, so they are repelled from magnetic field (and - 3rd law of dynamics - equally repell magnets)

Superconducting magnets are something quite different - they are ordinary electromagnets with yokes makes of some ferromagnetic substance (iron, ferrite...), but their coils are made not of copper wire, but rather of superconducting wire - which may conduct extremely high current without any resistance, so without dissipating any power, which - in case of copper coil - would melt it quickly.
 
  • #3
So that means that the permanent magnet is not being attracted to the superconductor but is instead being repelled and the superconducting magnets are not permanent magnets but electromagnets with the difference being that the superconducting electromagnet has no resistance.

But if this is the case then why did one experiment video show a superconductor following the permanent magnet when it was lifted away and yet it was also repelled when the permanent magnet was pushed too close. Additionally, this superconductor was only cooled by liquid nitrogen and it had no power supply which means that it is a permanent and not electromagnet.

But then again, the superconductor needs no persistent mass magnetic field to be attracted to a permanent magnet because permanent magnets can attract metals even when those metals are demagnetized and exert no external magnetic field. This is due to the many excess electrons possessed by metals being attracted to the external magnetic field. The only question is why the permanent magnet can be attracted to the superconductor but not to the point that it sticks to the surface of the superconductor?
 
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1. What is a permanent magnet?

A permanent magnet is a material that has a magnetic field and retains its magnetic properties even after being removed from an external magnetic field. Common examples include refrigerator magnets and compass needles.

2. What is a superconducting magnet?

A superconducting magnet is a type of magnet that uses a superconducting material, which has zero electrical resistance at very low temperatures, to generate a strong magnetic field. They are commonly used in medical imaging, particle accelerators, and research facilities.

3. How do permanent and superconducting magnets attract each other?

The attraction between permanent and superconducting magnets is due to the magnetic fields they produce. Permanent magnets have a north and south pole, while superconducting magnets have an induced current that produces a magnetic field. These opposite poles and fields attract each other, resulting in a strong and mysterious attraction.

4. How does temperature affect the attraction between permanent and superconducting magnets?

Temperature plays a crucial role in the attraction between permanent and superconducting magnets. As the temperature of a superconducting magnet increases, the induced current decreases, resulting in a weaker magnetic field. This can decrease the strength of the attraction between the two magnets. On the other hand, temperature does not affect the magnetic field of a permanent magnet, so its attraction remains constant.

5. What are the potential applications of exploring the attraction between permanent and superconducting magnets?

Studying the attraction between permanent and superconducting magnets can lead to advancements in various fields, such as energy storage, transportation, and medical technology. It can also help us better understand the properties of superconducting materials and their potential uses in different industries.

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