Tell me about constructive vs. destructive wave interference.

Thank you so much!!!!!

Think about two waves, like waves travelling along a string. If the two waves are superimposed (placed on top of each other), their amplitudes will add together to form the resultant wave. If you imagine all the peaks (highest points on the wave) meeting with the peaks of the other wave, the resultant wave will have an amplitude at it's peaks of twice the amplitude of one of the original waves. This is constructive interference - when two or more waves are superimposed such that the peaks meet.

Destructive interference is when the peaks of one wave meet with the troughs (lowest points) of the other wave. If both waves have the same amplitude this results in complete cancelling of displacements (ie: there will be no resultant "wave" just a flat line).

Hope that's what you were looking for, i can go into more detail in an edit if you want