Acoustic Radiometer spins in 130dB sound, clockwise and counter-clockwise depending on sound pattern

Demonstration of a rotor that is turned by sound pressure. It can spin either direction depending on what type and pattern of sound is applied. I also test different gases (hydrogen, sulfur hexafluoride, carbon dioxide, and helium) in addition to air at different pressures. Dan Russell's video of the radiometer: https://www.youtube.com/watch?v=KGLFJzFt-G4 Academic paper on the radiometer: https://sci-hub.ru/10.1119/1.1645287 Laser cutter used to make the rotor vanes: https://www.cloudrayla