Talk:Orders of magnitude (magnetic field)

re:move
Field strength is typically H, flux density is T. Sorry about that..

Thric3 (talk) 05:07, 25 March 2008 (UTC)

Instant death field
The source provided for the "0.1 MT - (10^5 T) - Magnetic field instantly lethal to organic life." claim is dubious. Can anybody find that information on a more trustworthy site?72.224.14.144 (talk) —Preceding comment was added at 16:32, 4 June 2008 (UTC)


 * I agree and removed the reference 128.104.84.146 (talk) 17:15, 5 June 2008 (UTC)

Strongest continuous magnetic field, need for a revision?
This article from 2006 defines HTS Bitter Selonoids for making 50T magnets.

http://accelconf.web.cern.ch/AccelConf/e06/PAPERS/WEPLS108.PDF

--Nevit (talk) 08:54, 16 March 2010 (UTC)

Planck magnetic field
If I have calculated correctly, the Planck unit of magnetic field strength is approximately 2.15 * 10^53 T. —Preceding unsigned comment added by 75.33.44.61 (talk) 12:53, 4 October 2010 (UTC)

Magnitude of human brain magnetic field
Reference? 128.171.61.158 (talk) 08:43, 28 April 2013 (UTC)

Found one: http://workshop.ee.technion.ac.il/upload/Events/Andrei.pdf 128.171.61.158 (talk) 08:48, 28 April 2013 (UTC)

Magnetic field needed to levitate a human?
I noticed the magnetic force needed to levitate a frog is 16T. Is there some way to calculate how much magnetic force is needed to levitate a human? — Preceding unsigned comment added by 131.251.252.33 (talk) 21:20, 23 October 2013 (UTC)

Many links are outdated or wrong
links 12, 13 and 14 are not working — Preceding unsigned comment added by 193.206.81.47 (talk) 17:11, 10 February 2015 (UTC)

Magnetic fields from 1kT to 1MT
The whole area in the table is missing and should be covered, explosive-driven EMP generators work on the giga gauss scale, in general. But this is no laboratory condition, of course...

next, I don't see collapsing ring magnetic fields anywhere... forgot the scientific name for those, if you have an iron and copper ring one inside of the other and induce current in it, it can collapse and compress the inner ring of copper, the current grows to some insanely high levels. The purpose is just for lab and science... I saw it in Tsukuba university papers somewhere. — Preceding unsigned comment added by 46.149.115.252 (talk) 11:59, 7 April 2017 (UTC)

Suggestions
I'd like to find some sources so we can add :
 * a range for fridge magnets (it says 5 mT) - seems there is a [wide] range.
 * a value for the neodymium 'rattle snake' toys
 * a value for the welders tool to hold steel at 90 degrees.
 * The cardic/pacemaker device limit could say where one might be subject to such a field (eg in public or industrial settings?) ?
 * What field is experienced sat over a motor on the various London underground lines ?
 * MRI scanners - can we give a range for whole body scanners ? - Rod57 (talk) 10:54, 17 May 2020 (UTC)

Precise measured stat for fridge magnets would be nice
https://www.magnetshop.com/flexible-magnets.html says "Grade F1" flexible have Residual Flux Density (Br) of 1,600 gauss. That matches https://rochestermagnet.com/technical-magnet-data/ which provides a list of a bunch of other magnets and includes 1,600 gauss "Flexible Regular". It also gives ceramics as between 2,300 gauss to 3,850 gauss. Those flexible and ceramics are I would guess are what are used for "frigerated" magnets...but those values a way higher than the "50 gauss" or "100 gauss" that this article's table currently uses.

(I also found https://www.kjmagnetics.com/neodymium-magnet-specifications.asp which gives a bunch of values for neodymium grades, which seem to match the neodymium example in this article's table...which leads me to think we should use the rochester magnet's table for values of Br.)

I don't know if the "50" and "100 gauss" numbers are using some other method of measurement than the "Residual Flux Density (Br)". But it seems to me this article's table should use a consistent standard for giving these magnetic field strengths, in which case I would say just copy the values for "flexible" and "ceramic" from the rochestermagnet url rather than the "50" or "100 gauss". Em3rgent0rdr (talk) 08:27, 29 December 2023 (UTC)


 * another table of ferrite ceramic grades https://e-magnetsuk.com/ferrite-magnets/grades-of-ferrite/ are all above a kilogauss for Br.
 * Another page that talks about strength https://www.first4magnets.com/us/how-is-the-strength-of-a-magnet-measured-i1409 gives
 * 100 Gauss – A typical refrigerator magnet
 * 1,100 Gauss – Magnetic rubber grade Y
 * 3,700 Gauss – Ceramic magnets
 * Yet again there is the loose quote of a "typical fridge magnet" being "100 gauss". But that is lower than "rubber grade Y" and "ceramic" (maybe those aren't considered "typical fridge magnet"). And somehow another page https://www.adamsmagnetic.com/blogs/magnet-blog-what-you-need-know-about-gauss/ gives "10 gauss" for "refrigerator magnet"... But I would think there must be some standard material with a specific code name for the material used for fridge magnets, like all these url tables seem to have pretty standard entries like "Ceramic I" and "Ceramic V" and "Y26H-1" and "N35", etc. These fridge magnet companies must have specific standard names for the grades of their fridge magnet material.
 * So I'm wondering if we could find what is the code name(s) for the specific grade of the "typical fridge" magnets, then at least we have a certain datapoint for this table. Em3rgent0rdr (talk) 08:47, 29 December 2023 (UTC)
 * Resolved my issue mostly. I found some more loose quotes for fridge magnets, and I grouped multiple rows in the table to give the range of fridge magnets.  Though some good source with actual measurements would be nice.
 * Also the Residual flux density (Br) is probably not good numbers to use for actual field strength that a user would find on a particular point on the magnet, became geometry of the magnet is very important, not just the grade of the magnet's material. What I ended up doing was finding a calculator and cooked-up some inputs that give a nice power-of-ten datapoint for "penny-sized" N38 disc of 1,000 gauss on surface center, and a 10 cm disc-shaped ring of 10,000 gauss in center of 1.6mm hole. Em3rgent0rdr (talk) 22:00, 29 December 2023 (UTC)
 * That would be original research, which isn't a substitute for a reliable source. Yappy2bhere (talk) 00:04, 8 April 2024 (UTC)

Invisible comment from the "Orders of magnitude" table
Would be nice to have a datapoint for bare minimum (i.e. the minimum gauss required to hold the fridge magnet itself up against gravity) and datapoint for strongest ones that can hold other object like light kitchen objects on them. Another point to be aware of is these fridge magnets often are polarized with a halbach array pattern, so they don't have a fixed gauss at every point on the magnet but rather the strength oscillates in bands between high perpendicular field strength to low field strength parallel to the surface, so it is not clear whether these are quoted as peak perpendicular field strength or some sort of average. Precise data points with actual measurements would be nice. Em3rgent0rdr (talk) 05:26, 30 December 2023‎ (UTC)