A beam of light in the air encounters a transparent block with an index of refraction. Part of the light is reflected and part is refracted.
Not. Reflection approaches 100% as theta approaches 90 degrees. At 90 degrees there is no incident light, so you get 100% 0 or 0 reflected light. See ref.
Source(s): http://hyperphysics.phy-astr.gsu.edu/hbase/phyopt/…
http://en.wikipedia.org/wiki/Equations_de_Fresnel
This is the angle of “total internal reflection” and only occurs when changing from a higher index material to a lower index material.
So it won’t happen when going from air to a higher index medium (glass is about 1.5). This occurs when changing from water (1.3) to air (1.003 or more). So, for fish looking up, from certain angles the surface of the water looks like a mirror.