Dr. V:Invisible Ink

HONOLULU (HawaiiNewsNow)- Dr. V is back with a cool experiment the shows the power of magnets and ink! Kids make sure to get your parents help with this experiment.

Dr. V Show: Ferrofluid

September 28, 2010

Things you need:

  • Ferrofluid
  • Magnets
  • Plate or bowl

The experiment

Please perform this and all experiments under the supervision and with the assistance of an adult. You can purchase ferrofluid from educational or science supply stores. Please be careful when handling ferrofluid, it will stain fabric. Also be very careful if you are using rare earth, or neodymium magnets, they can pinch with great force if you happen to get a finger caught in between them. Try pouring some ferrofluid in your bowl, what does it look like? How does it behave? Now slowly bring your magnet close to the bowl. What happens to the fluid? Move your magnet around under the bowl, or move it farther away from the bowl. Wheat happens to the ferrofluid?

How does it work?

The ferrofluid looks and behaves like a liquid, but when you place a magnet near it, it looks like a solid! The fluid takes the shape of the magnetic field, so you can actually see the magnetic force of your magnet. Ferrofluid is a mixture of extremely small magnetic particles, like magnetite or hematite, suspended in an oil or solvent. Ferrofluids are used in a variety of applications, and are commonly used in loudspeakers for the heat transfer properties. The ferrofluid removes heat from the loudspeaker, making it an efficient cooling method which requires no additional energy input.

Copyright HawaiiNewsNow 2010