4 Mechanical Waves Waves that require a material medium Examples include ocean waves; ripples in water; seismic waves; sound, and waves along a spring or rope; wave of people at a sporting eventThese materials carry the energy of the wave
13 Longitudinal WaveParticles of medium to move parallel to the direction of the waveExamples include sound waves, waves through fluids, liquids, gases or plasma
14 Compressional Wave (longitudinal) A mechanical wave in which matter in the medium moves forward and backward along the same direction that the wave travels.Ex. Sound wavesA slinky is a good illustration of how a compressional wave moves
15 Parts of a Compressional Wave (Longitudinal) The compression is the part of the compressional wave where the particles are crowded together.
16 Parts of a Compressional Wave (Longitudinal) The rarefaction is the part of the compressional wave where the particles are spread apart.
17 Surface Waves Mixture of transverse and longitudinal waves Example: At the surface of the water, particles move parallel and perpendicular to the direction of the wave.
18 Electromagnetic Waves Waves that DO NOT NEED matter (medium) to transfer energy Examples: radiation, TV & radio waves, X-rays, microwaves, lasers, energy from the sun, visible light Electromagnetic waves are considered transverse waves because they have similar characteristics; therefore, they have the same parts.