Give the characteristic of stationery waves.
(i) Stationary waves are produced in a bounded medium. A medium whose boundaries are separated from other media by distinct surface is called bounded medium. The boundaries of a bounded medium may be rigid or free. (ii) There are certain points in the bounded medium which are always in the state of rest. These points are called nodes. If the stationary waves are longitudinal, then the change in pressure and density is maximum at nodes as compared to the other points. (iii) There are points between the nodes whose displacement is maximum as compared to other points. These points are called anti-nodes. In the longitudinal stationary waves, there is no-charge in pressure and density of the medium at anti-nodes. (iv) The distance between any two successive nodes or antinodes is λ/2. The distance between a node and the neighbouring anti-node is λ/4 (v) All the particles between two successive nodes vibrate in the same phase. They pass simultaneously through their mean positions and also pass simultaneously through their positions of maximum displacement. (vi) Stationary waves do not advance in the medium, but remains steady at its place. (vii) All the particles except those at nodes, execute simple harmonic motion about their mean positions with the same time period. (viii) In a stationary wave, the medium splits up into a number of segments. Each segment vibrates up and down as a whole.
