Transverse wave
From Wikipedia, the free encyclopedia
A transverse wave is a moving wave that consists of oscillations occurring perpendicular to the direction of energy transfer. If a transverse wave is moving in the positive x-direction, its oscillations are in up and down directions that lie in the yz-plane. A transverse wave could be represented by moving a ribbon or piece of string, spread across a table, to the left and right or up and down.
[edit] Properties
The properties of transverse waves are exemplified by ripples in water, the vibrations of a stretched string and electromagnetic waves. In transverse waves, the molecules of the medium oscillate perpendicular to the direction of propagation, whereas in longitudinal waves, the molecules of the medium oscillate parallel to the direction of propagation. In seismology transverse waves are called secondary, or s waves because they arrive later than the primary, or p waves from an earthquake, which are longitudinal. The inability of s- waves to travel through the earth’s outer core shows that it is liquid.
[edit] Examples
Examples of transverse waves include seismic S (secondary) waves, and the motion of the electric (E) and magnetic (M) fields in an electromagnetic wave, which both oscillate perpendicularly to each other as well as to the direction of energy transfer. Therefore an electromagnetic wave consists of two transverse waves, visible light being an example of an electromagnetic wave. See electromagnetic spectrum for information on different types of electromagnetic waves.
An oscillating string is another example of a transverse wave; a more everyday example would be an audience wave.
