1. Chapter 11 vocabulary Medium: matter through which a wave travels
Wave: disturbance that transmits energy through matter or space
Mechanical Wave: wave that requires a medium through which to travel
Rarefaction: when coils of a longitudinal wave are stretched out
Surface waves: occur at a boundary between 2 different mediums, such as air and water

2. 6. Longitudinal wave: wave that causes particles of the medium to vibrate parallel to the direction the wave travels. Ie sound waves
Seismic waves: wave that travels through earth
Crest: highest point of a transverse wave
Hertz: Si unit for measuring frequency Hz
Trough: lowest part of a transverse wave

3. Speed of light: 3 x 108 m/s or 186,000 mi/s
11. Tsunami: huge ocean wave caused by earthquakes
Transverse wave: wave causes the particles of the medium to vibrate perpendicularly to the direction the wave travels-ie light
Doppler effect: an observed change in frequency of a wave, when the source of observer is moving
Speed of light: 3 x 108 m/s or 186,000 mi/s
Wave speed: the speed at which a wave passes through a medium ,
v=f x λ

4. 16. electromagnetic spectrum: full range of light at different frequencies and wavelengths
17. Period: the time required for one full wavelength to pass a certain point
Electromagnetic wave: wave caused by the disturbance in electric and magnetic fields, doesn’t require a medium- also called light wave
Wavelength: the distance between 2 successive identical parts of a wave
compressions: coils of longitudinal waves that are bunched up

5. 21. Damped harmonic motion: a vibration that fads out as energy is transferred from one object to another
wave front: wave spread out evenly and spherically from the source
Simple harmonic motion: when motion is continuous forever
amplitude: greatest distance that particles in a medium move form their normal position when a wave passes
Standing wave: wave form caused by interference that appears not to move along the medium and that shows some regions of no vibrations(nodes) and other regions of maximum vibrations (antinodes)

6. 29. Node: no vibrations in a wave
26. Antinodes: regions of maximum vibrations
27. Frequency: the number of vibrations that occur in a 1 second time interval
28. Pitch: how high or how low a sound is, determined by the frequency at which sound waves strike the eardrum
29. Node: no vibrations in a wave
30. Destructive interference: any interference in which waves combine so that the resulting wave is smaller than the largest of the original waves

7. 31. interference: combination of two or more waves that exist in the same place at the same time
reflection: bouncing back of a wave as it meets a surface or boundary
Constructive interference: interference in which waves combine so that the resulting wave is bigger than the original waves
Refraction: bending of a wave as they pass form 1 medium to another
Diffraction: the bending of a waves as it passes an edge or an opening