Interference of waves

Instructions on how to use the animation below:

• The sources (red discs):
  • Drag the discs in order to change their location
  • As you drag the sources, their x and y coordinates will appear in a yellow box in the lower left hand corner of the animation
  • Click on the button marked "Add" to produce one or more additional sources
  • Click on the button marked "Delete" to delete all of the sources
• Other:
  • Click on "Stop" to pause the animation and forward to resume play of the animation
  • Click on "Step>>" or "<<" to move the animation forwards or backwards in time, respectively, one frame at a time
  • Click on "Edit" to stop the animation and edit the properties of the sources (e.g., their location and how many there are)