One of the experiments in our physics lab manuals has students determine the speed of sound in air by creating a short sound in a column of air, such as a hollow tube. A Vernier Microphone is used to pick up the initial sound and the echo of the sound from the end of the tube.
Sample data collected with a clicker and a fluorescent tube guard
A graph of the data allows the student to determine the round-trip time for the sound. Knowing the time and the round-trip distance, they calculate the speed of sound. One challenge in the experiment is to create a short enough sound that it dies out before the echo is received. We used to recommend snapping your fingers to create the sound, but some students struggle with that.
We’ve come up with a better solution: Use a dog training clicker, readily available at pet supply stores. It creates a nice sharp sound that dies out quickly. Here are some sample data collected with a clicker and a fluorescent tube guard cut off to 1.165 m. From this data, the speed of sound was determined to be 332 m/s at room temperature.