total internal refraction

• what is the critical angle?

  the angle of incidence when the angle of refraction is 90 degrees
• total internal refraction
• how does total internal refraction occur?

  when the angle of incidence goes past the critical angle
• what is total internal refraction?

  when the refracted ray no longer exits the medium
• what is seen in total internal refraction

  only the reflected ray
• THE TWO CONDITIONS FOR TOTAL INTERNAL REFRACTION

  1. the speed of light is faster in the second medium
  2. the angle of incidence is past the critical angle, which makes it large enough to not let refraction occur in the second medium, only the first
• applications .
• diamonds

  sparkle due to the angles which the stone was cut to have more total internal refraction
• fibre optics

  cable material is made to have total internal refraction as to not let light escape
• triangle prisms

  reflect almost 100% of light, used in binoculars to reflect 90 degrees
• retro-reflectors

  shaped like triangle pyramids, return incident light back to where it came from to see it