Introduction to Superposition Principle Waves
The result of overlapping a couple of waveform is obtained by adding algebraically each of the sine waves that make up that complex motion. If we superpose sinusoidal waves of equal frequency, but with possible different amplitudes and phases, we will obtain another sine wave with the same frequency, but with different amplitude and phase. Although the decomposition of any complex motion into an overlapping of different proportions of simple harmonic motions is strictly true for periodic complex motions, certain mathematical approximations allow us to decompose non-periodic motion into a set of simple motions as well. The amplitude varies as a cosine, implying that there are points for which the amplitude of oscillation is null. These points are called nodes. The points in which the amplitude of oscillation is maximum are called antinodes.