Introduction to High Resolution Spectroscopy 

Introduction Rotational Vibrational Miscellaneous

Interference Between Waves
  
 

When waves meet one another, they interfere. When a peak meets a peak, or a trough meets a trough, the interference is constructive and the waves add together to give a new wave with a greater amplitude. When a peak meets a trough however, the interference is destructive and the amplitude is decreased - if both waves are the same size then the result is zero amplitude.

In the simulation below, the blue wave and the green wave are travelling and interfere with one another to give the resulting red wave. As they are travelling, the relative phase between them changes and so the interference changes from constructive to destructive.



The simulation can be changed in a number of ways:
  • change the frequency of each wave using the sliders
  • change the velocity of the waves using the slider
  • reverse the direction of one of the waves using the button
  • press the mouse button to freeze the simulation at any point
  • press and drag the mouse near the top of one of the peaks to change the relative amplitudes of the two waves
  • press the drag the mouse near the centre line so change the relative phase
  • press 'f' to remove the red wave
  • press 'reset' to start the simulation again
 


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