Physics Color and Light
Complementary Colors
2 colors (one primary and one complementary) that make white light
Spectroscope
An instrument that separates light into a spectrum into ROYGBIV
Why is red apple red?
Because red light is reflected and all other colors are absorbed.
Why is mid-day blue but evening sky looks reddish why
Blue light is scattered, but at sunset/rise, blue light is COMPLETELY scattered only red/orange is left over.
What colors make cyan?
Blue, Green
High freq appear
Cyan
Primary Colors of Pigment
Cyan, Yellow, Magenta
What colors of ink are used to print full-color pictures in books and magazines?
Cyan, Yellow, Magenta, Black
Subtractive Color
Formation of colors by removing some wavelengths of light, leaving less light than was originally there. Magenta, Yellow, Cyan
How could you use the spotlights at a play to make the yellow clothes of the performers suddenly change to black?
If the yellow clothes are illuminated with blue light, no color will be reflected and they will appear black.
How can yellow be produced on a screen if only red light and green light are available?
Overlap the red and the green
The process of producing a color by mixing pigments is called color mixing by subtraction. Why do we say "subtraction" instead of "addition" in this case?
Pigments subtract light
Primary Colors of Light
RBG
What colors make up white light
ROYGBIV
White light
ROYGBIV
What colors make magenta?
Red, Blue
What colors make yellow?
Red, Green
What colors of spots are lit on a television tube to give full color?
Red, Green and Blue
What is light scattering?
Redirection of light in multiple directions
Why are more and more fire engines being painted yellow green instead of red?
The human eye is most sensitive to yellow-green
Mix all and it creates
White
Low freq appear
Yellow
What color is the complement of blue?
Yellow
ON a TV screen, red, green and blue spots of fluorescent materials are illuminated at a variety of relative intensities to produce a full spectrum of colors. What dots are activated to produce yellow? Magenta? White?
Yellow- red and green; magenta- red and blue; white- red, blue, and green.
What is the color of common tennis balls, and why?
Yellow-green tennis balls are highly visible. Our eyes are most sensitive to yellow-green.
Suppose two beams of white light are shone on a white screen, one beam through a pane of red glass and the other through a pane of green glass. What color appears on the screen where the two beams overlap? What occurs if instead the two panes of glass are placed in the path of a single beam?
Yellow; all the light is absorbed.
. What color would a yellow cloth appear if illuminated with sunlight? With yellow light? With blue light?
Yellow; yellow; black
ROYGBIV are in the order of
increasing frequency
When low and high freq combine, they make
magenta
Black color
the absence of light --absorb light of all visible frequencies
Additive Color
works by superimposing lights, putting more light in the mixture than exists in any one light by itself Red, Green, Blue
