An Experiment About Slippery Bananas Led To Some Really Useful Findings
They were designed to make people laugh, but the Nobel Prize parody awards known as the Ig Nobels have actually brought attention to some hard-hitting scientific discoveries.
While uncovering the mystery of what makes banana peels so slippery, for example, a team of Japanese physicists nailed the fruit's hidden quality that could someday help engineers craft a flexible artificial joint for a prosthetic limb.
As it turns out, the same type of slippery-smooth gels that make banana peels slide also help lubricate our joints. Underneath their brown and yellow exterior, banana skins are lined with hundreds of tiny sacs of the gooey substance, which the scientists dubbed "polysaccharide follicular gel."
We have a similar substance in our own bodies called synovial fluid. It lines the places where our elbows, knees and other joints slip-and-slide and keeps the bones from rubbing together and wearing away. When all those tiny sacs in the banana skin get compressed-or stepped on-they burst, forming a single super-slimy surface prime for slippage.
To land on their finding, the scientists first tested the slipperiness, or friction, of a banana peel on a linoleum plate (to mimic how much a shoe on the fruit would slide on a typical floor) and compared it with how much a shoe would slide on a banana-free floor. A small tool called a "force transducer" was used to measure exactly how much sliding took place.
The shoe on a banana peel was far more slippery (and less frictional, as shown in the chart below), than a plain old floor.
Not to be outdone by other fruits, the researchers compared the slippery qualities of a banana peel with those of other pieces of produce, including apples, oranges and tangerines.
Not surprisingly, the banana skins were the least resistant to slippage. Learning more about the material that makes banana peels so slippery could help engineers created a synthetic substance with the same qualities needed to make artificial limbs behave more like real ones.
Who says fruit is just for eating?