5H10.35 - Magnetorheological Fluids

Code Number:
Demo Title:
Magnetorheological Fluids
Magnetic Forces & Field Lines
Area of Study:
Electricity & Magnetism
Plexiglas ramp, magnet, glass tray, magnetorheological fluid.

Place the ramp over the tray at a steep angle.  Pour some of the fluid into the top of the ramp and watch as it slowly travels downward.  You can stop the downward motion by bringing a magnet close to the underside of the ramp.  Observe the fluid closely during this operation and you will see that it seems to solidify when the magnet is brought near.

The solution is a mixture of iron filings and vegetable oil.

  • James E. Martin, Kyle J Solis, "Mesmerizing Magnetic Fields", Physics Today, Aug. 2015, p. 66.
  • Simon Quellen Field "Magnetorheological Fluids", Gonzo Gizmos, 2002, p. 4.

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