I recently read about a switchable (ON/OFF) permanent magnet. [link]
This intrigued me, and caused me to imagine a half-baked version, the variable strength permanent magnet. Simply include a variable control to adjust the relative positions of the two magnets, and viola!
Not to be confused with magnetic monopoles.-- csea, May 05 2015 (?) ON/OFF permanent magnet http://us9.campaign...a44399&e=42d7a30a0cInspiration [csea, May 05 2015] This is already Baked to a certain extent by winding a coil around a permanent magnet and then passing a current so that the resultant field opposes the permanent magnet.
It means that the force can be varied from zero, through P which is the force of the permanent magnet with zero coil current, to P + D where D is the additional force of the coil at maximum current.
This is pretty much how remanence relays work.
The coil must not heat the core above its Curie point.-- 8th of 7, May 05 2015 The "on/off" magnet assemblies linked (well, linked to the link) don't come right out and say it's variable, but it sure looks that way.-- FlyingToaster, May 05 2015 Would a half-on magnet have East and West poles?-- MaxwellBuchanan, May 06 2015 East Poles? Blimey, is everyone carving off a chunk of Ukraine nowadays?-- bs0u0155, May 06 2015 It does look likely .. we'll Czech on it and get Baku to you ...-- 8th of 7, May 06 2015 random, halfbakery