Speed of the sound in air: a homemade experiment with microcomputer and pail of water

This paper proposes a homemade experiment for the determination of the speed of the sound in air. For that, a computer program was developed for the audio generation in frequencies provided by the user, and also for the presentation of the experimental manuals (high school and college). The proposed experiment was accomplished by several students, at home and the obtained results agree with the expected values.