Wave Forms
Longitudinal – A longitudinal wave has the same direction of vibration, and particle movement, as the direction of travel. A Slinky, the kid’s toy, is one example. The coils in the Slinky are being displaced in the direction of travel.
Transverse – A transverse wave is oscillating perpendicular to the direction of travel, unlike the longitudinal wave that is in the same direction of travel. Its particle movement is up-and-down (in the example below) as opposed to the left-to-right movement of the longitudinal wave (in the example above).
Wave Motion
Traveling – A traveling wave, as the name implies, is a wave that is moving. It may be either longitudinal or transverse, but will move in the direction of propagation. The top image is longitudinal, traveling waves. The bottom is a transverse wave.
Standing – A standing wave is a stationary wave, remaining in a constant position. An example might be an ocean wave that has a peak that is constantly five feet from the shoreline, never traveling to the shore. The wave moves up and down, peaking at a few feet above sea level and then dropping a few feet below sea level, always in the same place. A standing wave can form when two waves of equal amplitude and frequency are traveling in opposite directions.
Constructive and Destructive Waves
Constructive Waves –the interference of two or more waves of equal frequency and phase, resulting in their mutual reinforcement and producing a single amplitude equal to the sum of the amplitudes of the individual waves.
Destructive Waves – the interference of two waves of equal frequency and opposite phase, resulting in their cancellation where the negative displacement of one always coincides with the positive displacement of the other.