Snell's Law:
* Angle of Incidence (i): The angle between the incident ray and the normal (a line perpendicular to the surface at the point of incidence).
* Angle of Refraction (r): The angle between the refracted ray and the normal.
* Index of Refraction (n): A property of the medium that indicates how much light bends as it passes from one medium to another.
Snell's Law states:
n1 * sin(i) = n2 * sin(r)
where:
* n1 is the index of refraction of the first medium
* n2 is the index of refraction of the second medium
Key Points:
* Directly Proportional: The angle of refraction is directly proportional to the angle of incidence, meaning if the angle of incidence increases, the angle of refraction also increases.
* Refraction: When light travels from one medium to another, it changes direction. This is due to the change in the speed of light as it passes from one medium to another.
* Index of Refraction: The index of refraction determines how much the light bends. A higher index of refraction means more bending.
Example:
If light travels from air (n1 = 1.00) to water (n2 = 1.33) with an angle of incidence of 30 degrees, you can use Snell's Law to calculate the angle of refraction:
1.00 * sin(30°) = 1.33 * sin(r)
sin(r) = (1.00 * sin(30°)) / 1.33
r = arcsin(0.3759)
r ≈ 22.1°
In Summary:
Snell's Law provides the mathematical relationship between the angle of incidence and the angle of refraction. This law is fundamental to understanding how light behaves when it passes from one medium to another.
