"Published in Newark, California, USA"
A layer of ice lies on a glass plate. A ray of light makes an angle of incidence of 60° on the surface of the ice. Find the angle of refraction in the ice and the angle of refraction in the glass.
Solution:
The given problem is about refraction of light in which the speed of light will change as it passes through the material. There's a bending of ray of light also in the material. To illustrate the problem, it is better to draw the figure as follows
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| Photo by Math Principles in Everyday Life |
According to Snell's Law, the index of refraction is inversely proportional to angle of refraction. The higher the value of index of refraction, the smaller the angle of refraction is.
From the Table of Index of Refraction, the index of refraction of air at 20°C is 1.000, ice at - 8°C is 1.310, and glass (crown pure) is 1.500.
Since there are three materials in the refraction, then we need to consider two materials one at a time in solving for the angle of refraction.
For air and ice, the angle of refraction of air to ice is
Finally for ice and glass, the angle of refraction of ice to glass is
