What are “superfluids”?
YES! Just what Reeko likes to see – a kid interested in learning! Check back here every week to see what the new Science Word of the Day is. Just think, after a year of this you’ll be a genius! This science word for today is: “Superfluid”.
From the strange but true department, a superfluid is a liquid that flows without friction. Its properties produce some very bizarre behaviors. For instance, if liquid helium is cooled to -452 degrees Fahrenheit, it becomes a superfluid and will suddenly be able to do things that no other liquid is capable of doing. If you took a glass of water and twirled it around until the liquid inside was spinning, and then set that glass on the table and left it for 10 minutes, when you came back it would have settled down and stopped spinning. But not superfluid helium. You could walk away and come back 1 million years later and the superfluid helium would still be spinning in the glass.
A key to helium’s superfluid effect is its ability to maintain its liquid state when cooled to absolute zero (-459.67 degrees F). Most liquids will freeze into a solid at temperatures far above absolute zero. But not liquid helium. The atoms in liquid helium are very light and not attracted to each other very strongly (kind of like you and that kid that sits next to you in chemistry class).
Superfluids display other weird characteristics too. For instance, their frictionless characteristic allows it to flow through cracks in a glass jar, cracks so small that we cannot even see them. Scienctists discovered this strange property when they cooled liquid helium in a glass jar and were amazed when the liquid suddenly began seeping through the walls of the glass, like a ghost passing through a solid wall.
All fluids put into a container will rise up on the walls of the container just a bit. But the liquids internal friction will only allow it to rise by a very small amount. But not superfluid helium. Superfliuid helium will climb the walls of the container and continue spilling over until all the contents of the container have been siphoned off.
The studies of superfluid helium have already produced three Nobel Prizes with studies beginning to creep into an area called “supersolids”. Scientists believe if supersolids are proven to exist, a new form of matter will be added to your school text books.