Professor Bruce Drinkwater demonstrates an ultrasonic fountain. A 1MHz focused ultrasonic transducer is used to create an effect known at the ultrasonic fountain. The ultrasonic waves create an acoustic radiation pressure on the surface of the water. As the intensity is increased the water surface is deformed. At high enough acoustic intensities water drops are ejected and a fountain is formed. At yet high intensities, the water is vaporised.
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