How can I successfully recreate the Einstein - de Hass Effect experiment?

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Discussion Overview

The discussion centers around the replication of the Einstein-de Haas Effect experiment, exploring practical methods for conducting the experiment and the availability of resources or kits for assistance. Participants share their experiences and challenges in attempting to recreate the experiment, as well as insights into its significance in the field of magnetism.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant describes their attempts to replicate the experiment using various methods, including fishing line and bearings, while expressing frustration over the lack of resources available online.
  • Another participant mentions a kit available from the University of New Mexico that reproduces the experiment, suggesting it as a potential resource.
  • There is a discussion about the recognition of the experiment, with one participant expressing surprise at its perceived obscurity despite its association with Einstein.
  • Another participant counters that the experiment is significant, noting its relevance to understanding the orbital moment of electrons in magnetism and mentioning alternative measurement methods.
  • One participant shares their difficulty in finding information about the experiment through various search methods, highlighting the challenges in accessing relevant literature.

Areas of Agreement / Disagreement

Participants express differing views on the recognition and importance of the Einstein-de Haas Effect experiment, with some asserting its significance while others question its prominence in the literature. The discussion remains unresolved regarding the best methods for replication and the availability of resources.

Contextual Notes

Participants note limitations in available resources and the challenges of finding comprehensive information about the experiment. There is also mention of language barriers in accessing certain archives.

DFingles
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How do I replicate the Einstein - de Hass Effect experiment? I know the basic premise: hang a slender iron rod inside a ring magnet and it should spin as the electrons all line up, to conserve angular momentum. Are there any websites detailing how to conduct/build/recreate this experiment? I've tried several times to find any and got zilch each time. So I moved on to experimenting. I've tried several ways, including using fishing line (can't make it taut enough to not shift to one side as the line stretches); swivels soldered to the ends of a rod and connected to hooks while the magnet sits on a wooden base (the tension breaks the solder, even JB Weld won't hold, and it's really tough to get an absolutely straight connection across a weld). I've also tried iron magnets and rare Earth magnets (use gloves when handling these--there's a safety lesson in there somewhere). Now I'm going to try fixing the rod inside bearings at either end to hold it rigid. The bearings are fixed to a structure and the magnets will sit on a wooden beam midpoint along the rod. Am I barking up the wrong tree?
 
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I've never heard of this before...strange. I know of the de Haas-van Alphen Effect, and the Shubnikov-de Haas oscillation, but not this one. Looks like de Haas has immortalized himself through great collaborative work.

Anyway, I found a kit (for sale) that reproduces this experiment. The kit is made by the Physics Demo group at the University of New Mexico. You can either try and speak to someone there, or simply buy the kit to see how it's built.

http://www.unm.edu/~physics/demo/html_demo_pages/5H5010.html

Can't do better than this right now, but someone is sure to come along with better advice.
 
Thanks for the info. It seems amazing that for someone as famous as Einstein (and De Haas) that this chapter has gone pretty much unrecognized. Maybe it's just not important (unless you're trying to duplicate it).
 
The experiment is not unrecognized or unimportant. The magnetomechanic ratio tells us about the orbital moment of the electrons involved in magnetism. Now there are also other ways of measuring this, but these methods require more theory and are less direct.

X-ray magnetic dichroism gives reasonable agreement with Einstein-de Haas data:
http://prola.aps.org/abstract/PRL/v75/i1/p152_1
 
Pieter; Unless you're a physicist, I beg to differ. I've tried numerous searches through Google, Gallileo (Ga University Library System), local library, etc. All I got for my trouble was a quizzical look (most of the time), some Japanese briefings, a description of properties for magneto-optical drive calibration, and only through this site an actual picture of a duplicate of the experiment. Even the Einstein archives doesn't have it in English (unless you're willing to fork over a membership fee, maybe-I wasn't able to convince my wife that was a necessary expense to find out).
 

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