Wave propertiesWavefront – a line joiningpoints that are in phase - the lines you seewhen ripples spread onwater are wavefronts Rays – arrows drawn to show the direction of wave motion
Reflection- The bouncing ofwaves off a surfaceRegular reflection –reflection from a smoothsurface - an image wouldappear to be coming frombehind the surface
Diffuse reflection –reflection from a non-smooth surface - light bounces offthe surface but no imagecan be seenWhen light hits a surface, part of the wave is reflected,part is absorbed by the atoms of the material.When light hits a transparent material, some istransmitted through the window.
Law of reflectionThe angle of incidence equals theangle of reflectionAll angles are measured to thenormal line (perpendicular to thesurface)
RefractionWhen a wave passes from one medium intoanother, its velocity changes. If the wave hits theboundary at an angle, the wave also changesdirection.
Light travels at 2 x 108 m/s in a substance. What is itsindex of refraction?The index of refraction of a liquid is 0.80. How fastdoes light travel in it?