State the principle of superposition of waves and illustrate it schematically.

Whenever two or more waves travelling through the same medium at the same time pass through each other, the net displacement of the medium at any point in space-time is simply given by the sum of the individual wave displacements.An easy way to illustrate this schematically would be by sketching both constructive and destructive cases using sine and cosine waves. More complicated waveforms could them be later also considered (square, triangular, etc...).