What are the potential uses for ferrofluids in interactive museum displays?

[Crystian]

Hi there;

Right now I am currently in both a second level introductory college level Chemistry and Physics course. In chemistry, we have a semester project to do, and with a little physics background, we are going to create our own Ferrofluid.

We need to figure out different things we can quantify. For any of you who have done any sort of work with Ferrofluid, what are some things we should be interested in trying to measure, or be interested in looking at?

Any sort of advice would be great,
Thanks in advance!

 

[Andy Resnick]

Measuring the coercivity seems logical. Perhaps some dynamic experiment that compares the magnetic properties with the viscous properties could be interesting- for example, try and create waves with a time-varying magnetic field.

 

[Bobbywhy]

Here’s a paper that seems to include part of what Andy Resnick above suggested. It may provide some ideas for your project:

“Sound damping in ferrofluids: Magnetically enhanced compressional viscosity
INTRODUCTION
Ferrofluids are colloidal suspensions of mono- or subdomain ferrimagnetic nano-sized particles suspended in a carrier liquid. Under the influence of an external magnetic field the fluid behaves paramagnetically. Among the more remarkable flow phenomena of ferrofluids are the enhanced effective shear viscosity in a static magnetic field, or the viscosity decrease in response to an AC-field. Both are due to the so-called magneto-dissipative effect, which occurs when the experimental time scale compares to the magnetic relaxation time.”

http://arxiv.org/abs/cond-mat/0211297v1

Bobbywhy

Edit: Please don't forget the remarkable behavior of this curious fluid under the influence of magnetic fields. Museums have found interactive displays of this are very popular.