Waves

2. crest is the highest point the medium rises to.
3. point:maximum amount of displacement of a particle on the medium from its rest position.
8. spectrum:the range of wavelengths or frequencies over which electromagnetic radiation extends.
10. compression is a region in a longitudinal wave where the particles are closest together.
12. SI unit of frequency, equal to one cycle per second.
14. period T is the time needed for one complete cycle of vibration to pass a given point.
17. is the reduction of an item's density, the opposite of compression.
19. Interference: the interference of two or more waves of equal frequency and phase.
21. object or device that focuses or otherwise modifies the direction of movement of light, sound, electrons.
22. the maximum extent of a vibration or oscillation, measured from the position of equilibrium.

1. distance between successive crests of a wave, especially points in a sound wave or electromagnetic wave.
4. number of crests of a wave that move past a given point in a given unit of time.
5. is the change in direction of a wavefront at an interface between two different media so that the wavefront returns into the medium from which it originated.
6. reflective surface, now typically of glass coated with a metal amalgam, that reflects a clear image.
7. wave:A transverse wave is a moving wave that consists of oscillations occurring perpendicular to the direction of energy transfer.
9. Interference:the interference of two waves of equal frequency and opposite phase.
11. substance that makes possible the transfer of energy from one location to another, especially through waves.
13. process by which a beam of light or other system of waves is spread out as a result of passing through a narrow aperture or across an edge.
15. fact or phenomenon of light, radio waves, etc., being deflected in passing obliquely through the interface between one medium and another or through a medium of varying density.
16. is measured in Hertz (Hz), with one vibration per second being equal to one hertz (1 Hz).
18. wave:a wave vibrating in the direction of propagation.
20. trough is the lowest point the medium sinks to.