For Friday

Hi.

Let's be sure that we understand Snell's law.  With that in mind, answer the following questions:

1.  What is an index of refraction?

2.  What is Snell's law, and what do all of the symbols represent?

3.  Draw a picture that represents a light Ray hitting a piece of glass at an angle of 30 degrees with respect to a normal (perpendicular) line.

4.  In the problem above, if the light 

is refracted to an angle of 14 degrees, what is the index of refraction of the glass piece?  Light comes in from air.

5.  Now, a light Ray hits a new material with index of 1.8, at an angle of 45 degrees.  What is the angle of refraction inside the material?  

6.  What exactly is a critical angle?

Thank you.