Expert: Scotto - 2/10/2009

Question
When a light beam passes from one medium to another, (for instance, for air to water), it changes both its speed and direction. According to Snell's Law of Refraction below, describes the relationship between the speed of light in the first medium v1, its speed in the second medium v2, the angle of incidence θ1, and the angle of refraction θ2, as shown in the figure. The number v1 / v2 is called the index of refraction. The index of refraction of light passing from air to glass is 1.54. If the angle of incidence is 29°, find the angle of refraction.

Sinθ1     V1
----- =  ----
Sinθ2     V2


θ2 = ????



PICTURE (http://img.photobucket.com/albums/v384/peaches323/math2.gif)




I can't figure out how to set this up and get the answer..  

Answer
The equation is sin(Θ1)/sin(Θ2) = V1/V2.
We have been told that Θ1 = 29° and
that the index of refraction is 1.54.

I believe the index of refraction is V1/V2,
so the equation to solve is
sin(29°)/sin(Θ2) = 1.54.

Multiply both sides by sin(Θ2) and dividve
both sides by 1.54.  What you get is
sin(Θ2) = sin(29°)/1.54.

All that is needed to solve this is to know
Θ2 is between 0 and 45° somewhere, so when
you take calculate the right side and take
the inverse sin() { known as arcsin() },
it should give it to you.

By the way, I couldn't find your address,
so I just did a search for anything containing
photobucket.com v384 peaches, and it didn't turn up.