Reflection & Refraction Flashcards
How does regular reflection occur?
On smooth, shiny surfaces.
How does diffuse reflection occur?
On rough, dull surfaces.
What is reflection?
When light or sound waves hit a surface and bounce back.
What does the law of reflection state?
Θi = Θr
What are the properties of images that are produced on plane mirrors?
1) Virtual image
2) Up-right
3) Latterly inverted
4) Same size
5) Distance from object to the mirror = distance from mirror to image
Why does refraction occur?
Because substances have different densities.
Diff mediums -> diff densities -> diff light speed -> light-ray will refract
How does a refracted ray move (with normal) depending on its speed?
1) Towards the normal if it’s getting slower
2) Away from the normal if it’s getting faster
What is the speed of different mediums from highest to lowest?
Vacuum > gas > liquid > solid
What is the density of different mediums from highest to lowest?
solid > liquid > gas
What happens to a light ray when it travels from a low to a high density medium?
1) It slows down
2) Ray refracts towards the normal
3) Θr < Θi
What happens to a light ray when it travels from a high to a low density medium?
1) It speeds up
2) Ray refracts away from the normal
3) Θr > Θi
What happens to a ray that travels parallel to the normal?
It does not change direction but it slows down.
What is the equation for the refractive index?
sair
n = —————–
smedium
What is the speed of light in air?
3 x 10↑8 m/s
What is the equation to find the angles?
sinΘair
n = ————————-
sinΘmedium
