Science Solves the Perfect Ponytail PuzzleCassie Murdoch2/13/12 11:30amFiled to: HairponytailRapunzel numberPonytail shape equationRaymond goldsteinCambridgeEnglandshutterstockSciencetweetFb121EditPromoteShare to KinjaToggle Conversation toolsGo to permalinkEver have that problem where you don't know what your ponytail is going to look like on a given day? Well, science has just solved it for you—at least if you're willing to do a bunch of calculations first. British scientists say they've created a "Ponytail Shape Equation" which can predict the shape of any ponytail. The equation uses a measure of the curliness of hair, the stiffness of each hair, and something called the "Rapunzel number," which is a ratio that accounts for "the effects of gravity on hair relative to its length." Sounds a lot more complicated than just jamming your hair through a rubber band and seeing what comes out.AdvertisementApparently the aptly named Rapunzel Number was the key ingredient to solving a problem which has vexed us all since da Vinci first raised it 500 years ago. If this seems utterly useless to you in the mornings, fear not, this information will actually be helpful for people who deal with, "the structure of materials made up of random fibers, such as wool and fur, and will have resonance with the computer graphics and animation industry, where the representation of hair has been a challenging problem." At least if we can't use this equation to correct our own bad hair days, we can take comfort in the fact that our avatars' ponytails will be looking perfectly accurate.'Rapunzel Number' helps scientists quantify ponytails [Reuters]AdvertisementImage via takayuki/Shutterstock.