54 terms

# physics chapter 14 and 15

#### Terms in this set (...)

index of refraction
what does n stand for
speed of light over speed of light in the medium
refraction
speed changes because of change in medium changes direction
bends towards the normal
how does the ray behave if it slows down
bends away from the normal
how does the ray behave if it speeds up
frequency
what remains constant in refraction
slower the light moves
the higher the index of refraction
total internal
has reached the critical angle and bounces off second medium back into the first must go from a medium with a higher index to a lower index use snells law and make one of the angles 90 degrees
lens
light passes through it and is refracted
covex lens
acts like a concave mirror
concave lens
acts like a convex mirror
real
what type of image does a convex lens produce
virtual
what type of image does a concave lens produce
concave or divergind lens
negative focal point q is always negative and the image is always virtual and smaller
no
do all colors refract the same
spectrum because of different frequency
what happens when white light is refracted
refraction and reflection
why do we see rainbows
sun must be behind at a 40-42 degree angle
what are the conditions necessary for a rainbow
mirage
hot air on the ground lower index above higher index light from the sky is refracted
chromatic aberation
top of the lens acts like a prism image with a border of color slightly fuzzy
diffraction
speed doesnt change direction does
every point can be a point source
what makes a spherical light look like its traveling in one direction
energy of waves goes into a shadow region it follows the barrier and becomes a point ource
what happens in difraction
interference
happens when diffraction occursboth sides of the barrier let waves through and they hit
constructive interference
equal wavelengths apart bright light and antinodes
destructive interference
1/2 of an odd wavelength dark and a node
because they all behave like a point source
why do the wavelengths curve in diffraction
bright (antinode) to dark node
describe the light reflection of diffraction
2 x as big in the middle
describe the reflection of a single slit
backwards
d is the width of the opening not distance between slits
constructive and destructive flips
describe what happens to a single slit
recipricol
how do you find d when given a difraction grating
shortest wavelength is difracted the least
longest is difracted the most
describe what happens to a spectrum of light in a dirfaction grating
diffraction
direction changes and spreads past the barrier
1
what is the index of refraction of air
interference
2 waves difract and hit each other
violet
what gets refracted the most
constructive difraction
crest to crest or trough to trough whole numbers 1 2 3
destructive
crest to trough 1/2 3/2 5/2
difraction
depends on wavlength
refraction
depends on speed
difraction grating
has multiple double slits put 1 over slits per cm to find distance between slits
frequency
what remains constant in refraction
wavelength is longer
what happens to the wavelength when it speeds up
wavelength is shorter
what happens to the wavelength when it slows down
towards the normal with a bigger index of refraction
describe what happens when is is slowed down in refraction
away from normal with a smaller index of refraciton
what happens in refraction when it speeds up
total internal refraction
high index of refraction to low index of refraction
away from the normal
critical angle
theta two is 90 degrees
smaller angle
describe the angle when it moves from a low index to high index
bigger angle
describe the angle when it moves from a high index to a low index
mirage
hot air on the bottom cool air on the top light is refracted from sky and it looks like water
rainbow
sun is behind hitting the raindrops in front slows down refracts total internal reflection is the reflected
converging lens
can project onto a screen
usually a real image unless it is inside focal point
f is positive p is positvie q is positive or negative
diverging lens
concave lens virtual f and q are negative
distance between slits
what is d in the difraction equations
take the inverse tangent of x over l and plug it into theta
how do you find theta when given x and l