Sound Wave
Light Sound and Waves

Whistling waveforms

Practical Activity for 11-14 IOP RESOURCES

In this activity, students download an oscilloscope app onto a laptop or phone to investigate pitch and loudness. You can use it to introduce waveforms of sounds.


Each student will need:

Teaching notes

Students should start by watching the video as described on the instruction sheet before downloading an oscilloscope onto a laptop or phone. For a Windows laptop, Soundcard Oscilloscope is ideal as it provides a large display for easy comparisons of wave traces. If your students do not have access to a laptop, alternative free apps for smartphones or tablets are suggested on the activity sheet. If you recommend a different one, make sure it has a pause function.

If students can’t whistle, they can ask another person at home to be their sound source. Alternatively, they could blow over bottles or use a musical instrument such as a guitar or a recorder. They should see that when the sound is louder the peaks of the waveform are bigger, and that when the pitch is higher the peaks are closer together.

Learning outcome

Students draw waveforms for sounds with different volumes and frequencies.

With thanks to Christian Zeitnitz for permission to use Soundcard Oscilloscope

2021 IOP Awards

Teachers of Physics Award

Recognising and celebrating outstanding contributions to the field of physics education.

Learn more