Magic Magnetic Fluid
Magnetic liquids respond to magnets by manipulating a pool of ferrofluid to make it "dance." Ferrofluid is a magnetic material made by suspending trillions of tiny iron particles in an oily liquid. The iron particles respond to magnetic fields, enabling ferrofluids to be used to fix leaks in oil pipelines, for example.Copyright Ontario Science Centre http://www.ontariosciencecentre.ca
Students are introduced to a unique fluid—ferrofluids—the shape of which can be influenced by magnetic fields. This activity supplements traditional magnetism activities and offers comparisons between large-scale materials and nanomaterials. Students are introduced to the concepts of magnetism, surfactants and nanotechnology by relating movie magic to practical science. Students observe ferrofluid properties as a stand-alone fluid and under an imposed magnetic field. They learn about the components of ferrofluids and their functionality as they create shapes using magnetically controlled ferrofluids and create their masterpieces.
Ferrofluids have been around since the 1960s when the uses were many, such as audio speaker coolants and high-end engineering seals. Dynamic rotary shaft seals are an example of high-end sealing technologies that are typically implemented by mechanical engineers in an industrial plant setting. More recently, this technology is the topic of research involving nano particle suspensions and engineering such materials to have greater magnetic properties under moderate magnetic fields. Materials engineers have developed new nanomaterials for medical applications targeted at localized drug delivery systems by an induced magnetic field. These engineers use basic chemistry and physics fundamentals, along with newly acquired nanoscience, to introduce particles small enough to transport through capillary systems and organs and have sufficient magnetization. Additionally, materials and biochemical engineers design biocompatible and biodegradable organic coatings to reduce toxicity levels and biochemical reactions that may occur with such magnetic nanomaterials in humans or animals. Most importantly the fluid must behave like a fluid until a magnetic field is applied.
After this activity, students should be able to:
- Explain magnetism theory.
- Relate differences in large scale magnetic materials and nano-magnetic materials.
- Describe the unique behavior of ferrofluids under magnetic fields.
- Describe applications and uses for ferrofluids.