11. Refractive Index

Question 1

What is the theory behind the refractive index?

Answer 1

Light travels at it’s fastest in a vacuum, which has a refractive index of 1, as it passes through materials such as glass, it slows down as this material is more ‘optically dense’ than a vacuum.

Question 2

What is the absolute refractive index?

Answer 2

The absolute refractive index of a material, n, is the ratio between the speed of light in a vacuum, and the speed of light in the material.

Question 3

What is the Relative refractive index between two materials?

Answer 3

The relative refractive index between two materials is the ratio of the speed of light in material 1 to the speed of light in material 2.

Question 4

What law deals with light passing through a boundary between two materials?

Answer 4

Snell’s law of refraction.

Question 5

What is Snell’s law if refraction?

Answer 5

Snell’s law of refraction is states that the refractive index of 1 material multiplied by the angle of incidence (the angle at which it enters the boundary) is equal to the refractive index of the second material multiplied by the angle of refraction (the angle at which it leaves the boundary)

It can be written as n1sinθ1 = n2sinθ2