3.28 describe an experiment to measure the speed of sound in air
Experiment: To measure the speed of sound by direct method
Apparatus: Starting pistol, stopwatch, measuring tape.
Procedure:
- By means of measuring tape, observers are positioned at known distance apart in an open field.
- First observer fires a starting pistol.
- Second observer seeing the flash of the starting pistol, starts the stopwatch and then stops it when he hears the sound. The time interval is then recorded.
Ways to improve:
- Repeat the experiment a few times and compute the values of the speed of sound for each experiment. Find the average value. This procedure minimizes random errors in finding the time interval between seeing the flash and hearing the sound.
- Observers exchange positions and repeat experiment. This procedure will cancel the effect of wind on the speed of sound in air.