Interference Between Two Sinusoidal Waves

In this applet you can see the result of superimposing two waves of different frequencies and amplitudes on top of each other. The resultant wave is the sum of the two waves.

You can set the amplitude and frequencies of the two waves. When you have selected the deired values, click on the centre panel to see the result.

This phenomenon is closely related to beats, which are seen when the two frequencies are close together. You can simulate this using the controls above by setting the two frequencies to almost the same value. Try experimenting with the amplitude controls, and in particular see the difference in the pattern when the amplitudes are equal, and when they are different from each other.

This next applet also shows the phenomenon of beats.