Talk:Rotating magnetic field

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Images and old pages[edit]

Image:3phase-rmf-noadd-60f-airopt.gif and Image:3phase-rmf-60fv2-airopt.gif was at Rotating magnetic field illustration. Moved here. Rotating magnetic field 19:12, 6 June 2006 (UTC)[reply]

I believe User:Rotating magnetic field is a sockpuppet of User:Reddi. --ScienceApologist 01:52, 15 June 2006 (UTC)[reply]

Believe what you want. Rotating magnetic field

I belive it too. Reddi has a severe revert limit imposed William M. Connolley 15:50, 15 June 2006 (UTC)[reply]
Believe what you want. What you believe isn't true. Rotating magnetic field

No evidence that Tesla identified the rotating magnetic field before 1888[edit]

There is no historical proof of that !! Please update the historical section givinig the right credit to the real descoverer: Galileo Ferraris.

We're working on it. ScienceApologist (talk) 21:44, 21 February 2010 (UTC)[reply]
According to Harvard University Professor of History; William L. Langer, who compiled and edited 'An Encyclopedia of World History', page 555, Nikola Tesla discovered the rotating magnetic field in 1877 which was what made the long distance transmission of electric power possible.174.1.40.37 (talk) 04:32, 22 December 2014 (UTC)[reply]
And the source cited in this article says Galileo Ferraris probably did. When trying to weigh RS you should take into account whether the source is reliable for the statement being made, re: a work specifically on the "electrification in Western society" vs a a general "An Encyclopedia of World History". When sources disagree you describe the disagreement. Also check the source, if it says 1877 its flat out wrong. Tesla claims he did it in 1882. Fountains of Bryn Mawr (talk) 19:44, 22 December 2014 (UTC)[reply]

"Rotating" Magnetic Fields[edit]

Magnetic fields neither move nor rotate but may change in magnitude and direction over time for any given point in space. This is definitional. The very title of the article is nonsequiter and compounded throughout.

As such, this is a nonsense article.

Instead, given a static magnetic field to one observer, to another observer in relative motion, the field is "rotated" in space-time (a Lorentz boost) such that there appears to be both a magnetic and an electric field. 2001:5B0:2BFF:EF0:0:0:0:3C (talk) — Preceding undated comment added 18:06, 23 May 2015 (UTC)[reply]


The figure in the article having the caption 'Rotating 3-phase magnetic field, as indicated by the rotating black arrow' doesn't make sense at all, because it can clearly be seen that at any particular time, the sum of the values (levels) is equal to zero. For example, when phase A is maximum (eg. equal to 1 unit), then phase B and C are both at level of -0.5 units, so the total is 0. So, there needs to be some other diagram that shows very clearly just how a rotating field can be generated with three phases. For example, it needs to be pointed out that the three main field axis lines (for the three coils) are spaced 120 degrees apart physically. So the three-phase waveforms are not just spaced 120 degrees apart in time. The field axes themselves are also spaced 120 degrees apart (physically). So now, when field A is a maximum of 1 unit, the values of the other field lines will both be at -0.5 units (each). However, the extra key piece of information is that those two levels of -0.5 units must then each be 'physically' spatially resolved into the 'A' axis direction using trigonometry to become approximately equal to -0.25 (in the 'A' direction). When 'spatial' considerations are made, the negative values of B and C fields turns out to 'support' or reinforce the 1 unit A field. This is because if (for example) two vector fields are 'drawn' to have directions (arrow symbols) that oppose each other, then one field quantity being assigned a positive value and the other field quantity being assigned a negative value will mean the two actual fields will 'support' each other - merely due to sign convention. So the combination of the B and C field (each ending up being +0.25 units in the same direction as the 'A' field) will combine to give +0.5 units in the 'A' field direction. This results in a total of (1 + 0.5) or +1.5 units (total) in the 'A' field direction. So the rotating vector will have a magnitude of 1.5 units. KorgBoy (talk) 22:42, 4 March 2020 (UTC)[reply]

Link to wrong Walter Baily[edit]

The page contains a link in the History section to the wrong Walter Baily. It links to Walter Lewis Baily Jr the 20th century American mathematician, not Walter Baily the 19th century electrical engineer. Sadly, there appears to be no Wikipedia page for the correct Baily.45.26.49.244 (talk) 19:49, 28 May 2022 (UTC)[reply]