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T.I.R flashcards

LeonieB Inglés 5 fichas

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1What is T.I.R? - total internal reflection When a light ray hits the boundary between 2 materials of different densities Beyond a certain angle, the angle become critical so all the waves reflect back so it is known as T.I.R.When does T.I.R occur?
two conditions:
angle of incidence > critical angle (90o)
The light must pass from a medium with a higher refractive index to a medium with a lower one. e.g. water to air
2—What are uses of T.I.R.?
Optical fibers are thin rods of glass which use T.I.R to bounce light rays through the rod until it reaches the other end.
T.I.R can also be used by doctors to see inside patients by using endoscopes.
3How to calculate the T.I.R: Sin c = nr / ni Sin critical angle = angle of reflection/angle of incidenceHow to calculate the critical angle:
Sin c = 1/η
Sin critical angle = 1/refractive index
4How to calculate refractive index: η= sin i/ sin r η= sine of the angle of incidence/ sine of the angle of refraction Refractive index of: air: 1.0002 water: 1.333 crown glass:1.517 dense flint glass: 1.655 diamond: 2.417Critical angle:
Refraction - angle of incidence < critical angle
Refraction along boundary - angle of incidence = critical angle
T.I.R. - angle of incidence > critical angle
5—This is an example of T.I.R. in real life