elementcollector1 - 28-11-2014 at 16:29
While doing research online, I came across this device - basically an automobile shock absorber that utilizes electromagnetic force and a magnetically
responsive fluid (rather akin to ferrofluid, but apparently not quite the same).
What I'm wondering is, how exactly do these work?
All I can find is that there is a change in viscosity when the magnetic field, but how does this change absorb force or energy - is it simply that the
thicker fluid absorbs more, or must it be continuously varied?
In addition, what kind of scale of force absorbed can these things do - no papers I've read say anything, so it could be anything from a few newtons
to a few kilonewtons.
IrC - 28-11-2014 at 18:56
Seems to be quite a lot of information about them:
http://en.wikipedia.org/wiki/Magnetorheological_damper
http://en.wikipedia.org/wiki/Magnetorheological_fluid
Attachment: poynor.pdf (2.9MB)
This file has been downloaded 519 times 
If you read the fluid page I believe it answers your question.
[Edited on 11-29-2014 by IrC]