Standing Wave (2 fixed ends, third harmonic)
- 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.
- The distance between two adjacent nodes is 1/2 the wavelength.
- There are 4 nodes in the 3rd harmonic; the length of the string equals 3/2 the wavelength.
- The frequency of the 3rd harmonic is 3 times the fundamental frequency for this string.