Ch 7: 4.24.19 Weekly Quiz material Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

draw/label a diagram demonstrating a principal axis… something (help me out here Dalton, what’s this one about specifically?)

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

draw/explain the elements of destructive interference.

A

valley to peak = 180 degrees out of phase = smaller/no wave

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

waves adding together to make a bigger wave

A

constructive interference

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what is an example of diffraction grating?

A

the color spokes from a CD (compact disc)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

the point where reflected rays intersect in a concave mirror

A

real focal point

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

draw/label a diagram of a converging lens and a diverging lens.

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

why do swirls of color appear in parking lot puddles?

A

there is a layer of oil on top of the water. light partly reflects off of the oil and partly refracts off of the water, so one incident ray becomes two reflected rays. the thickness of the oil layer causes one color to cancel out via destructive interference and we see its complement.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what causes a mirage of a water puddle on a hot road?

A

the air just above the road is hot, so a boundary is made between the hot air and the air above it. light crosses the boundary and severely refracts (basically reflects), and we perceive the light as coming from a puddle (self note: why water? b/c it’s a reflection of the blue sky). as we get closer, the angle changes and the mirage disappears.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

how waves interact

A

interference

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

draw/explain the elements of constructive interference.

A

peak to peak, valley to valley = in phase = bigger wave

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

light with random orientation

A

unpolarized light

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

why are sunrises/sunsets red?

A

as sunlight travels through the thicket part of the atmosphere, colors are being absorbed. red is the least absorbed and reaches us the best.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

why does the blue sky look dark with polarized sunglasses?

A

the scattered light that makes the sky blue is partially polarized so the sunglasses act as a second filter.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

draw/label a diagram of a concave mirror.

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

when an object is farther away than the center point of a concave mirror, how will the image be?

A

inverted, reduced, and real

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

a curved mirror with light reflecting off the inside surface

A

concave mirror (converging)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

2 examples of total internal reflection?

A
  • fiberoptic cables
  • water fountains lit from the bottom
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

age-related farsightedness

A

presbyopia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

two examples of a convex mirror?

A
  • the outside part of a spoon
  • security mirrors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

draw/label a diagram of a convex mirror.

A
21
Q

when an object is closer than the focal point of a concave mirror, how will the image appear?

A

upright, enlarged, and virtual.

22
Q

what causes hyperopia? what corrects this?

A
  • the lens can’t work with the eyeball and focuses light too far back.
  • a converging lens corrects this.
23
Q

light with a specific orientation

A

polarized light

24
Q

what causes presbypoia, and what corrects it?

A

1) over a lifetime, the lens becomes less flexible and focuses light too far back.
2) a converging lens corrects this.

25
Q

nearsightedness

A

myopia

26
Q

how a wave bends around a corner

A

diffraction

27
Q

why do diamonds show flashes of color?

A

dispersion causes the colors to separate out

28
Q

why is the sky blue?

A

air molecules absorb sunlight and release the energy as scattered light. violet is the color that is scattered the most, but our eyes see blue better.

29
Q

equation: focal length

A

focal length is radius over two.

(thus, R = f * 2)

30
Q

why can we hear a vacuum down the hall but can only see it if within line of sight to the door?

A

light waves don’t diffract well around a doorway, but sounds waves do

31
Q

why is the secondary rainbow fainter with the colors reversed?

A

for the secondary rainbow, the light bounces twice in the droplet and loses some energy.

32
Q

why does a grain silo seem to shimmer on a sunny day from across a field?

A

as the reflected light travels above the field, the air current causes the light to slightly refract one way or the other

the reason stars twinkle is similar (self note: air temperature difference is the reason for air currents to begin with)

33
Q

why is the mid-day sun yellow-white?

A

as sunlight travels through the thinnest part of the atmosphere, less colors are absorbed, so what reaches us is a better mix.

34
Q

a curved mirror with light reflected off the outside surface

A

convex mirror (diverging)

35
Q

how does a rainbow form?

A

the observer is between a water droplet and the sun. light goes into the droplet (refraction) and bounces inside (total internal reflection). the colors spread out (dispersion) and come out the front of the droplet. depending on the angle of view, we see one of the colors.

36
Q

why is the sky sometimes a hazy white?

A

particles in the air scatter other colors than blue, but then the colors mix back together to give a hazy white effect.

37
Q

the point where reflected rays seem to originate in a convex mirror

A

virtual focal point

38
Q

when different wavelengths spread out

A

dispersion

39
Q

how do polarized sunglasses work?

A

light that reflects off of water or chrome is partially polarized, so the glasses act as a second filter to block the glare.

40
Q

when an object is at any distance from a convex mirror, how will the image appear?

A

upright, reduced, and virtual.

41
Q

what word describes diamonds showing flashes of color?

A

“fire”

42
Q

two examples of a concave mirror are?

A
  • the inside part of a spoon
  • mirror surface of a headlight
43
Q

waves trying to cancel each other out to make a smaller (or no) wave

A

destructive interference

44
Q

why are clouds white?

A

clusters of water droplets scatter different colors of light based on their size. these colors mix back together to make a white cloud.

45
Q

when an object is between the focal point and the center point of a concave mirror, how will the image appear?

A

inverted, enlarged, and real.

46
Q

can our eyes tell the difference between polarized and unpolarized light?

A

no.

47
Q

what word describes a bright and shiny diamond?

A

“brilliance”

48
Q

why are diamonds bright and shiny?

A

good total internal reflection causes the light to come out at the top

49
Q

what causes myopia? what corrects it?

A
  • the lens can’t work with the eyeball and focuses light too soon
  • a diverging lens corrects this