Standing Wave (a fixed end and an open end, fundamental mode)
Two counter-propagating traveling waves (the 1st and 2nd waves) form a standing wave (the 3rd wave).
Each point in a traveling wave performs a simple harmonic motion. Adjacent points oscillate out of phase, but no point is stationary at all times.
Nodes in the standing wave: at any given momoent, the displacements of the two traveling waves are always equal in magnitude and opposite in direction, thus the sum forming a node.
There is one node at the fixed end in the fundamental mode; the length of the string equals 1/4 the wavelength.
