Wave Fronts

• Wavefronts are shown by the crests

  Rays show the direction of wave movement

  
• LAW OF REFLECTION: an angle of reflection (θr) is measured from the normal and is equal to the angle of incidence (θi) when also measured from the normal

  $θi=$$θr$
• Diffuse reflection is when waves reflect off an irregular surface, reflecting in varied directions
• Echoes: reflected sound waves
• Reverberation is when waves are reflected multiple time on different surfaces causing the sound appear longer and occurs in small rooms.

  -> to reduce echoes rooms can be furnished with acoustic foam sheets, rugs and textiles. All of which with the purpose to absorb sound.