Physics Ch 28

who was the first person to do a systematic study of color

Isaac Newton

name 3 statements true of Isaac Newton

a. he studied sunlight
b. he passed sunlight through triangular shaped pieces of glass
c. he observed that sunlight was broken into a rainbow like pattern of colors

a spread of colors

spectrum

list the visible colors

red, orange, yellow, green, blue, violet

true or false: sunlihgt is a combination of all colors

true

a white ocjects appears what color when illuminated by white light

white

white and black are not actual colors; explain

white is a combination of all colors while black is an absense of all light

true or false: black objects that you can see absorb all light that falls on them

false

name on fact tjhat describes a opaque object

an opaque object is the color it reflects

different materials have different what for absorbing and emmiting radiation

natural frequencies

describe what happens when the frequency of the light shining on an object resonates with the object's natural frequency

object absorbs the light

decribe what hjappens when the freqeucny of the light shining on an object is higher or lower than the objects natural frequency

objects remmits the light

true or false: when an object reemits the light that shines on it, absorption occurs

false

why do cells containing chlorophyll are green

they reflect green light

true or false: different sources of light produce light made up of different freqeucies

true

what determines the color of a transparent object

the color of the light it transmit

describe what happens when sunlight passes through the blue glass

the blue glass is absorbing all colors but blue, so it reflects the blue light

what is a material in glass that selectively absorbs colored light

pigment

what explains what the energy form the light absorbed by a piece of glass does to the glass

the energy warms the glass

true or false: human vision is most sensitive to colors in the red-orange part of visible spectrum

false

the graphical distribution of brightness versus frequency in sunlight is called what

radiation curve

true or false: the brightness of sunlight is directly proportional to frequency

false

what is the brightness portion of the spectrum of sunlight

the middle of the yellow/green range

what color of light is produced when red, blue, and green ligth of equal brightness overlap

you get white light

what colors do you get from a mixture of red and blue

magenta

what colors do you get from a mixture of red and green

yellow

what colors do you get from a mixture of green and blue

cyan

true or false: by mixing red, blue, and green light and adjusting the brightness of each, virtually any color can be formed

true

red, blue, and green light are known as the what colors

additive primary

explain how a color television produces a wide range of colors on its screen

they group spots of red, blue, and green which make magenta, cyan, and yellow

two colors of light that when added together produce white are known as what

complimentary colors

what is magenta's complementary colors

green

what is yellow's complementary colors

blue

what is cyan's complementary colors

red

what best describes the lgith that results when a color is subtracted from white light

the complementary color to the subtracted color

true or false: the mixing of colored paints yields similar results as mixing the same colors of light

false

explain what happens when paints or dyes are mixed

the mixture absorbs all frequencies

what color(s) are absorbed by blue paint

red, orange, and yellow

what color(s) are absorbed by yellow paint

blue and violet

if white light sines on a mixture of blue and yellow paint, what color is not absorbed

green

the mixing of pigments, paints, or dyes is known as color mixing by what

subtraction

magenta, yellow, and cyan are the what colors used in printing illustrations in full color

subtractive primary

describe the process used to print a color image in a book

they use black, magenta, yellow, and cyan to produce all colors

what is the process in which sound or light is absorbed and reemitted in all directions

scattering

true or false: atoms and molecules can behave like optical tuning forks

true

describe the relationship between the size of a particle and the frequency of the light it scatters

tinyier particle the higher frequency

true or false: the sky appears blue because particles in the atmosphere scatter low-frequency light

false

although ciolet light is scattered more than blue light, our eyes see the sky blue, why

our eyes are more sensitive to blue than violet

what occurs when many particles larger than oxygen and nitrogen molecules are in the atmosphere

the sky appears whitish

trur or false: the presence of water droplets in the atmosphere does not effect how much might is scattered or what frequencies of light are scattered

false

explain why many clouds appear white

they contain water droplets with wide ranges so they scatter to produce clouds

a cloud containing many large water droplets appear what

dark

the color of light that is scattered the least as it passes through the atmosphere

red

true or falso: at sunset light reaches Earth;s surface through a shorter surface than at noon

false

as the oath of sunlihgt through thr atmosphere increases, what color of light is scattered more

blue

describe how the color of the sky changes as more and more high frequency light is scattered

sky becomes redder; yellow to orange

true or false: at sunset, only lower-frequency light strikes Earth

true

true or false: the amount of scattering that occurs at sunset varies very little from day to day

false

true or false: water is tranparents to nearly all the frequencies of white light

true

true or false: the deep-blue color of a pond or an ocean is due to the color of water itself

false

color(s) that water molecules absorb

red

water molecules absorb certain frequencies of colored light. what complementary color is absorbed

cyan

true or false: when made to emit light, each element has its own unique color

true

what determines the colors emmited by an atom

energy levels of electrons

an enery level greater than an atom's lowest energy state is known as a what

excited state

after reaching an excited state, an atom emits a(n) what and returns to its normal state

photon

how is the frequency of a photon related to the energy change in a atom

directly proportional to the enrgy changed

what is a spectroscope

instrument usesd to measure light emmitted elements

true or false: the spectrum emmited by an excited atom is continuous

false

what does each line in a line spectrum represent

each line corresponds to a distint frequency of light emmitted by the atom