Travelling Waves: practical and virtual demonstrations

Use the links here to find demonstrations using sound and light.


Use a slinky: reflection of pulses (VUW activity with video, Shows reflection with inversion for transverse and reflection for longitudinal pulses.)
Use a rope
Use a long spring
Use a wave simulator machine (VUW instructions) or make a Gummy bear wave machine (for example the UK STEM video on Jelly Baby Wave Machine)

Sound and Light in a Vacuum
(VUW instructions) Light bulb and buzzer in vacuum jar. Light travels through vacuum but sound does not.

Doppler Ball (VUW activity with video)
A Doppler ball shows the Doppler effect qualitatively. Doppler Ball Frequency Shift Quantitative Video and audio analysis software are used to study the Doppler effect quantitatively.

Sound Interference
Sound interference illustrated with two speakers connected to a single signal generator

Diffraction and Interference of Water Waves (VUW)
Photos of water waves at an Eastbourne beach showing diffraction and interference effects.

Ripple Tank
Wave properties such as interference are demonstrated with a tabletop wave tank, displayed using an overhead projector.

Standing Waves on a Slinky
A slinky mounted on a frame is used to demonstrate transverse and longitudinal standing waves. Markers on the slinky make the oscillatory motion of the medium visible.

Beats are heard with two speakers connected to different signal generators set to slightly different frequencies. Video and audio files are provided.

Combining Sounds
Add two sine waves. Display the signal versus time, the Fourier Power Spectrum, and play the resulting sounds on computer speaker.

Rubens Tube: Sound Flames
The heights of flames from holes in a tube shows sound nodes and antinodes.

Tuning Fork Beats
Two tuning forks with slightly different frequencies give beats.

Tuning Fork Resonance
A tuning fork can easily transfer energy to another matching tuning fork, but not to one that resonates at a different frequency.

Square Wave Simulation
Add sine waves to make a square wave.

Standing Waves on a Wire
An AC electric current is used to excite standing waves in a wire passed over a magnet.


Phet simulation Wave on a String

Dan Russell’s moving images of different types of waves.

And Dan’s animations which show reflection of waves at different types of boundaries

Phet Ripple tank and wave interference

Superposition of waves  look for the animation

The Phet Sound simulation is also useful and can be used to show interference patterns.

Wave Simulator Software (VUW activity)
Adjust wave parameters and observe wave motion. An installer is available.