Chapter 28 (Physics)
when a sample of an element is heated until it glows, the color it gives off is
a composite of many frequencies of light
the reason the sky is blue is that air molecules
absorb and then reemit blue light, scattering it in all directions
Earth receives a lot of ultraviolet radiation from the sun. Luckily most of it doesn't reach the ground, because it is
absorbed by a protective layer of ozone gas in the upper atmosphere
colors seen on TV result from color
addition
red, green, and blue
additive primary colors
when blue and yellow paints are mixed together, the result if green. the reason for this is that
between blue and yellow pigments, all colors are absorbed except green
a photograph of your favorite person's yellow sweater shows as what color on the negative?
blue
if molecules in the sky scattered orange light instead of blue light, sunsets would be colored
blue
the white caps of waves as they overturn are evidence that the water has
broken into an assortment of tiny particles that scatter all colors
when two colors are added together to produce white
complementary colors
a sheet of red paper will look black when illuminated with
cyan light
a state with greater energy than the atom's lowest energy state
excited state
different colors of light correspond to different light
frequencies
if sunlight were green instead of white, the most comfortable color to wear on a hot day would be
green
the true color of water is
greenish blue
the colors of light emitted by incandescent gases show the
identities of atoms in the gas
a pattern of distinct lines of color with each line corresponding to a frequency of light
line spectrum
the complementary color of green is
magenta
when red and blue light shine on a white sheet, the resulting color is
magenta
the three paint colors that are useful for color subtraction are
magenta, cyan, and yellow
clouds are white because water molecules
of different sizes form clusters, scattering different colors of light
the material in the glass that selectively absorbs colored light
pigment
complementary colors are two colors that
produce white light when added together
the cyan color of ocean waves is evidence that the water absorbs
red
magenta light is really a mixture of
red and blue light
the colored dots that make up the color on a TV screen are
red, blue, and green
the three primary colors of light for additive color mixing are
red, green, and blue
if the atmosphere were 50 times thicker than it now is, the sun would appear
red-orange
the color of an opaque object is determined by the light that is
reflected
the sky is blue because air molecules in the sky act as tiny
resonators that scatter blue light
a process in which sound or light is absorbed and reemitted in all directions
scattering
spectral lines in a line spectrum take the shape of lines because the
slit of the spectroscope it itself a line opening
an instrument that light glowing from elements can be analyzed with
spectroscope
if you're looking for an instrument that tells what stars are made of, look for a
spectroscope
the spread of colors
spectrum
colors soon on a photograph result from color
subtraction
magenta, yellow, and cyan and are used for printing pictures
subtractive primary colors
light shines on a pane of green glass and a pane of clear glass. the temperature will be higher in
the green glass
a combination of all the colors
white light
sunlight contains all colors of light, but much of it is
yellow
the complementary color of blue is
yellow
when red and green light shine on a white sheet, the resulting color is
yellow
a tennis ball is most easily seen if its color is
yellow-green
humans are most sensitive to light that is
yellow-green