Sound Waves Experiment
Physics: Cambridge International GCSE Supplement, topic 3.6.6
Sound Waves Experiment
There are several ways to determine the characteristics of sound waves.
Measuring the speed of sound
- Method: Stand a known distance from a large wall (e.g., 50 m).
- Clap your hands or bang two blocks of wood together and use a stopwatch to measure the time taken to hear the echo.
- Calculation: Since the sound travels to the wall and back, the total distance is twice the wall distance.
- Speed of sound = (2 x distance to wall) / time for echo
Measuring frequency and wavelength
- Method: Connect a microphone to an oscilloscope, place it near a loudspeaker connected to a signal generator.
- Vary the frequency until you see a stable wave pattern.
- Measure the wavelength by moving the microphone and noting the positions where the signal is in phase (peak to peak).
- Calculation: 𝑣 = 𝑓𝜆
- Where 𝑣 is the speed of sound, 𝑓 the frequency from the signal generator, and 𝜆, the measured wavelength.