Wave interference: an experiment with two sources

What will you explore?

How does a ripple pattern change when a second source is switched on? In this experiment you will compare one source with two, then change the distance between them. Allow about ten minutes, with a mouse if you want to move either source independently.

Open the Ripples wave simulator. Keep this guide open in another tab so you can refer to the steps.

Set up a comparison

1. Choose Open in Borders and Heatmap in Color. Keep the same border, palette and resolution throughout the first comparison.
2. Turn 2nd Source off. Set Frequency to 2 and Amplitude to 12.
3. Press the simulator’s Reset button to clear existing waves. It keeps the current controls and source positions.
4. Watch the rings spread from the first source. Pause and use Save simulation image to keep a reference.
5. Resume, switch 2nd Source on, and reset the waves again. Watch the area where the two patterns overlap.

What should you look for?

Look for regions with larger and smaller oscillations. The two contributions can reinforce or partially cancel one another. The colors show the signed wave displacement using your selected palette; they are not a direct measurement of energy.

Both sources use the same frequency and amplitude controls. The second has a fixed quarter-cycle phase offset, so do not expect a textbook picture of two sources oscillating in phase. Patterns also change as waves reach the edges.

Change one thing

With a mouse, drag near the second source marker to move it closer to the first. Reset and compare after a similar observation time. Then move it farther away and repeat. On touch screens, dragging moves the first source; leave the second fixed and change their separation that way.

Keep a note of the source positions, frequency, amplitude and border setting with each image. Compare the arrangement of quieter regions rather than treating a single bright pixel as a result.

If the pattern is hard to see

Check that the second source is enabled. Try a different color palette, then keep it fixed for the next comparisons. Reset clears earlier waves; pausing freezes the image for inspection. Performance mode can help if animation is slow, but keep the same resolution when comparing runs.

Save and extend

Use Save profile to keep the parameters and source positions. A profile stores the setup, not a frozen wave field. Next, compare Open and Reflective borders while leaving everything else unchanged. This is a numerical visual model; use it to explore patterns rather than measure a physical ripple tank.