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George H.'s avatar

Oh my, well first you are working with ferromagnetism. Which theoretically is the weirdest type of QM and Thermodynamics and magnetism. And you should totally read about what everyone else has done.

Using the Earth's B field to do anything is fraught with danger, cause if a car drives nearby the local B field can change in all directions*. (The Earth's field is kinda weak on some scales.)

*at some point in my past life I was testing Rubidium optical pumping apparatus in the basement of my bosses house. Cars pulling in the driveway.. right next to my basement location, would totally flip the local B-field around. (Get a stronger magnet!)

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George H.'s avatar

Oh in some ways the 'natural' (lowest energy?) state of a hunk of iron/steel* is to be magnetized. You can search on ways to demagnetize your steel (tweezers). I've got an AC soldering iron one of these. https://www.weller-tools.com/bigbang/USA/us/D550PK

You can replace the soldering end with just a loop of copper, stick piece of iron into loop. turn gun on (creates changing 60 Hz. B field around steel object.) Turn off gun, the B field collapses to zero, but still back and forth which demagnetizes the piece of iron.

*Not all steels are magnetic. some are made to be non-magnetic

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Violet Henriques's avatar

Hi George, thanks for the insight! After a semester enrolled in a Physics II class (my first physics class!) I sort of understand what you are saying. I’m going to talk with my professor and see if she has any ideas :) or pointers on what parts of QM, thermodynamics, and magnetism are good spots to start reading (since they seem like difficult subjects to just ‘read what everyone else did’). Let me know if you have books or articles you want me to check out.

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George H.'s avatar

Ha, great. Don't just talk to your professors, but try grad students and upper classmen in physics too. Well one of my favorite physics books of all time are the Feynman Lectures on Physics. Free online from Caltech. You could try reading though the two sections on ferromagnetism (Vol II, chapters 36 and 37) But in some ways the Feynman lectures are only 'really good' after you already have a good background in physics. They are not that great to learn from.... partially because there are no after chapter problems to 'test' your understanding. Have fun!

George

https://www.feynmanlectures.caltech.edu/II_36.html

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