Hi, As part of my Physics Class, we created a spreadsheet that animates to waves moving in opposite directions to illustrate standing waves. In order to test we were told to put the same values of amplitude, wavelength and speed (frequency was calculated from wavelength and speed) for both waves. Our assignment was to try different values for amplitude and wavelength (to change the frequency) for each wave and to describe the effect. For some reason however, excel goes crazy and it is hard to observe the effect after changing these variables. Even though the animation is not working I wanted to submit my predictions. I am not very sure, but this is what I think would happen: If we have different amplitudes for each wave and pick equal values for wavelength and frequency for each wave I think that, during constructive interference, the resulting amplitude would add as it did before but during destructive interference, instead of having a node at 0 displacement we would have a node at negative displacement. For different frequencies for each wave, I don't see how it would work because, from what I understand, it only works when the two waves are coherent, correct? Thanks, Peter G.