Inquiring activities on the acoustic phenomena at the classroom using sound card in personal computer

Abstract

Inquiring activities on acoustic phenomena have been carried out in the classroom of a high school for highly gifted children. Instead of expensive instruments such as function generators and oscilloscopes, sound cards, installed in a personal computer, were employed for the generation and detection of sound. The stereo function of the sound card offered two sound sources, so that phenomena of interference and beats can be realized in the classroom. The record function of the sound card offered detection of sound, permitting frequency spectrum analysis of sounds from two tuning forks or the sound from a moving fork. Using sound card, a lot of acoustic phenomena can be demonstrated in the classroom. In addition, sound from Rijke tube, which is a typical theromacoustic phenomena, was analyzed by using a sound card. Popup sound of a wine bottle and breaking of wine glasses, which are related to resonace and standing waves, were also investigated. Curiosity of students was greatly increased through a series of inquiring activities with sound cards, so that they were completely absorbed in research on acoustics.