Scientists Use Sound Waves To Levitate And Manipulate Matter April 8, 2014 - A team of researchers in Switzerland have developed a way of levitating and transporting small objects using nothing but sound. Using ultrasonic waves that is, sound waves whose frequencies are too high for humans to hear, scientists at the Swiss Federal Institute of Technology in Zurich have made water droplets, instant coffee crystals, styrofoam flakes, and a toothpick, among other objects, hang in mid air, move along a plane, and interact with each other. It is the first time that scientists have been able to use sound to simultaneously levitate several objects next to each other and move them around. >As anyone with a subwoofer and a teenager knows, sound waves exert pressure. In the past, scientists have been able to acoustically levitate bits of styrofoam and even small insects and fish. “Theoretically there’s no difference between theory and practice,” says engineer Daniele Foresti, the study’s lead author, in a phone interview.
Magnetic levitation Magnetic levitation, maglev, or magnetic suspension is a method by which an object is suspended with no support other than magnetic fields. Magnetic pressure is used to counteract the effects of the gravitational and any other accelerations. Earnshaw's theorem proves that using only ferromagnetic or paramagnetic materials it is impossible to stably levitate against gravity; however, servomechanisms, the use of diamagnetic materials, superconduction, or systems involving eddy currents allow to achieve that. In some cases the lifting force is provided by magnetic levitation, but there is a mechanical support bearing little load that provides stability. This is termed pseudo-levitation. Magnetic levitation is used for maglev trains, magnetic bearings and for product display purposes. Lift[edit] where Stability[edit] Static[edit] Static stability means that any small displacement away from a stable equilibrium causes a net force to push it back to the equilibrium point. Dynamic stability[edit]