Refractions - Key definitions + Knowledge Flashcards
What is refraction?
Refraction is the change in velocity of light when it passes from one medium to another
What happens if ray goes from Less dense → More dense medium
Ray moves towards normal
What happens if ray goes from More dense → Less Dense medium
Ray moves away from normal
What is the absolute refractive index of a medium?
The absolute refractive index of a medium is defined as the ratio of the speed of light in a vacuum (c), to the speed of light in the medium (v)
What is the refractive index of a vaccum and of air?
1
What is the relationship between sinθa and sin θm
sinθa is directly proportional to sin θm
What happens to refractive index when frequency of light increases
Refractive index increases with increasing frequency of light
Why does a prism split white light into spectrum?
A prism splits white light into its spectrum of colour as the prism medium has a different refractive index for each colour of light.
Why does violet refract more than red light?
As violet light has a higher frequency than red light, the refractive index for the prism medium is greater for violet than for red light, so violet light refracts more.
What is critical angle?
the critical angle is the angle of incidence in a medium when the angle of refraction in air is 90o
What happens if the angle is increased past 90o (critical angle)?
No light is refracted and total internal reflection takes place.
