Lesson One : Types of Waves
Waves may be further classified as one of two types:Transverse waves: Transverse waves travel through space by oscillating perpendicular to their direction of motion. That is, they move from left to right by moving up and down. A familiar example would be the waves produced by holding one end of string and shaking it up and down rapidly. The resulting disturbances move along the string by making the string move up and down.
Longitudinal waves: As opposed to transverse waves, longitudinal waves travel by oscillating parallel to their direction of motion. Thus, a longitudinal wave that is moving from left to right is oscillating back and forth as it moves. Think of taking a SlinkyŽ, laying it on the ground, and shaking it back and forth. The oscillations that travel through the spring vibrate along its length.
Waves that must disturb a medium to propagate (like the ripples on the string, the compression and expansion in the SlinkyŽ, or the ripples in a pond) are further classified as mechanical waves.
A tranverse wave propagating through space by displacing the medium up and down.
A longitudinal wave propagating along a spring
A longitudinal pressure wave