By using the principle of reversibility of light the angle of incidence i in air and the angle of refraction r in glass can be found. In order to operate the tutorial use the Refractive Index of Material slider to change the composition and refractive index of the block between a range of 10 and 391. A The speed of light passing through a medium is 18 x 10 8 m s -1.
There is a mathematical equation relating the angles that the light rays make with the normal to the indices plural for index of refraction of the two materials on each side of the boundary.
For example for visible light the refractive index of glass is typically around 15 meaning that light in glass travels at c 15 200 000 kms 124 000 mis. Thats more than 10000 times the speed of the orbiting space shuttle. Likewise use n air theta air and n. For example a pane of window glass has a thickness that may be stated by the manufacturer but which should be measured to ensure accurate calculation of the refractive indexStep 2 Send light from a point light source through the object.