PURPOSE: To demonstrate standing sound waves in air excited by convection currents.
DESCRIPTION: A switch is held closed, activating a nichrome wire coil in a vertical plastic tube, leading to a very loud roar at about 130 Hz, the fundamental frequency of a four-foot air tube. This is the classsic Rijke tube demonstration with an electrical heater replacing a gas burner and screen as the source of the convection currents.
SUGGESTIONS:
REFERENCES: (PIRA 3D30.70) See Demonstration Reference File for further information about the theory and practice of Rijke tubes.
EQUIPMENT: Plastic tube with heater installed on rolling stand.
SETUP TIME: None.