| A | B |
|---|
| wave | a repeating disturbance that transfers energy through space or matter |
| medium | any substance that a wave travels through |
| vacuum | empty space |
| electromagnetic wave | a wave that does not require a medium to travel through |
| mechanical wave | a wave that requires a medium to travel through |
| transverse wave | a wave in which particles of matter vibrate up and down at right angles to the direction in which the wave travels |
| longitudinal wave | a wave in which the particles of matter move back and forth parallel to the direction in which the wave travels |
| crest | the highest point of a wave |
| trough | the lowest point of a wave |
| node line | the resting place of the material when no wave is present |
| node point | the points of a wave that do not move as they transfer energy |
| wavelength | the distance from a point on one wave to the same point on the next wave |
| frequency | the number of waves that pass a given point in a certain amount of time (usually per second) |
| compression | the part of a longitudinal wave where the particles are pushed together |
| rarefaction | the part of a longitudinal wave where the particles are spread out |
| reflection | the bouncing back of a wave after it strikes a barrier |
| refraction | the bending of a wave as it passes from one medium into another medium of different density |
| diffraction | the spreading out of a wave through an openning or around a barrier |
| interference | the adding up or canceling of two or more waves as they pass through a medium at the same time |
| constructive interference | the adding up of waves as they pass through the same medium |
| destructive interference | the cancelling out of waves as they pass through the same medium |
