Red Hot Magnetics Hypothetical Experiment

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Discussion Overview

The discussion revolves around a hypothetical experiment involving the interaction between a Neodymium magnet and a heated iron disk. Participants explore the effects of temperature on magnetic properties and the implications for the operation of the described setup, which includes a rotating iron disk beneath a stationary magnet.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant describes a setup where a Neodymium magnet is affixed to a stationary plastic disk above a rotating iron disk, questioning the effects of heating the iron disk on its interaction with the magnet.
  • Another participant expresses confusion about the purpose of the experiment and the expected outcomes.
  • A participant explains that iron above its Curie temperature behaves as a paramagnet, suggesting that the magnetic field's interaction with the heated iron disk may change.
  • A humorous remark is made about the physical danger of placing a hand between the two disks before the Curie temperature is reached.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the purpose or expected outcomes of the experiment. There are differing interpretations of how the heating of the iron disk affects its magnetic properties and interaction with the magnet.

Contextual Notes

Participants reference the Curie temperature of iron and its implications for magnetic behavior, but there are no detailed discussions on the specific mechanisms or calculations involved in the proposed experiment.

pallidin
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Hypothetical experiment:

I have a single 2-inch by 2-inch by 1-inch thick Neodymium magnet affixed on the outer rim of a 1-foot diameter circular hard plastic disk(1/8th-inch). The disk and magnet are held stationary by whatever means.
The underside of the plastic disk has a coating, an insulating coating, sufficient to withstand, let's say, 2000 degrees F with a coating thickness of 1/2 inch.
Fine.
Now, underneath this assembly I have another disk(same 1-foot diameter dimension), separated from the first disk by a nominal air-space. This second disk is allowed to rotate freely and in fact motor driven, unlike the first, which is held static.
The properties of this second disk is this: This disk is composed of iron(or other suitable ferromagnetic material) On the outside perimeter of this "iron" disk 2-inch diameter holes are drilled. With 2-inches between drillings, this provides for 6 holes on the outer rim of the 1-foot "iron" disk.
If I rotate this "iron" disk underneath the NIB magnet, a choppy "drag" will occur, due to the fact the iron disks' rotation will self-impede motion because of the magnet, yet the hole spaces provide relief, then drag. Choppy.
Now, let's heat the "iron" disk, very hot.
The "iron" disk, now super-heated and in rotation is not drag-affected by the magnet, but will spin freely.
Energy is used to heat the disk, so conservation is maintained.
However, the holes in the disk allows the magnetic field to pass during rotation of this heated disk, albeit in a pulsed manner.
Not getting something for nothing, but the question is this: Will this operate as I described?
 
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I really can't tell what this is supposed to do.

- Warren
 
Warren. What I am trying to understand is the interaction of a magnetic field with a red hot piece of iron.
A magnet will not attract red hot iron, does not repel it and does not go through it(if solid).
So what happens to the field if it doesn't do any of the above?
 
The curie temperature of Fe is around 1000C. When Fe is above it's curie temp. its thermal energy is large enough to cause random flips in the spin of electrons. Above the curie temperature Ferromagnets turn into a paramagnet. and you apply a magnetic field to a paramagent, the spins of the electrons try to align with the magnetic field.

JMD
 
What happens is, before the curie temperature is reached, you smash your hand between the two plates like a crepe
 

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