Lesson
What gives an object its color?
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83
LESSON
14
What gives an object its
color?
Joan's dress is red. Tornis wearing a blue shirt. Grass is green. An orange is
of course ... orange. Color, color, everywhere! Look around. How many
colors do you see?
What causes color in the objects we see? You have learned that when light
strikes an object, it can be reflected, absorbed, or transmitted. The color we
see depends upon whether the object is opaque or transparent. The color
also depends upon how much of the light is reflected, absorbed, or
transmitted.
OPAQUE OBJECTS The color of an opaque object is the color that it
reflects. For example, a red object reflects only red light. It absorbs all other
colors. A green object reflects only green light. It absorbs all other colors.
What about white and black objects? A white object reflects all the colors
that make up white light. A black object, on the other hand, absorbs all the
colors that strike it. No color is reflected.
Most objects reflect more than one color. The colors combine. We see them
as mixtures of colors, like blue-green and red-orange.
TRANSPARENT OBJECTS The color of a transparent (or translucent)
object is the color that passes through the object. For example, red glass
transmits only red light. It absorbs all other colors. Blue glass transmits only
blue light. It absorbs all other colors.
Ordinary window glass transmits all colors. White light that has passed
through window glass still has all the colors of white light. None of the
colors have been absorbed by the glass.
You have learned that some transparent substances transmit only some
colors. All other colors are blocked. These substances are called filters.
Filters are often used in spotlights and in photography.
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OBJECTS AND THEIR COLORS
Study Figures A through E. Answer the questions with each.
OPAQUE OBJECTS
1. List the colors that are striking the object in Figure A. _ __;__
-=-~
2. Together, these colors make up what kind of light?
_
3. List the colors that are being
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G B
I V
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G B
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V
reflected.
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__
4. Together these colors make up what
kind of light?
_
Figure A
5. The color of an opaque object is the color that the object
_
reflects, absorbs, transmits
6. What color is the object in Figure A?
7. How do you know?
_
-'-
---''--
_
8. List the colors that are striking the
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G B
I V
object in Figure B.
-'='-
_
9. All the colors are being
reflected, absorbed
10. None of the colors are being
reflected, absorbed
Figure B
11. The color of an opaque object is the color that the object
•
12. What color is the object in Figure B?
13. How do you know?
_
reflects, absorbs, transmits
_
_
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14. List the colors that are striking the object in Figure C. _ __;__--"''------"'--_-'-'"'--_..:.__
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G 8
I
15. List the colors that are being
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absorbed. -=..:.. __
----'><.--'~_-'J~
_
16. Which color is being reflected?
17. What gives an opaque object its
color? _-
_
Figure C
18. What is the color of the object in Figure C?
Why?
_
~
___
TRANSPARENT OBJECTS
19. List the colors that are striking the glass in Figure D.
--'-"---'-'....<.- __
---"0"-----'
_
20. Which of these colors is being
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?
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absorbed?
-'
__
R
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Y
21. Which color is being transmitted?
G
8
I
V
22. The color of a transparent object is
-
the color it
_
reflects, absorbs, transmits
Figure D
23. What is the color of the glass in Figure D? __
Why?
86
~
--'-
_
___
24. What is the definition of a filter?
25. Is this glass a filter?
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Why?_·
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_
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White light is striking the glass in Figure E.
26.
-
Are any colors being absorbed?
?
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27. All the colors are being
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y
G
reflected, transmitted
B
28. What kind of light is leaving the
v
glass?
_
'---
Figure E
29. Is this glass a filter?
Why?
_
~
___
30. Does this glass have a color?
_
31. What kind of glass is this?
32. Where can it be found?
_
_
REACHING OUT
blue
The colors of the American flag are red,
white, and blue.
What color or colors does each of these
colors reflect?
1. Red
2. White
3. Blue
Figure F
87
FILL IN THE BLANK
Complete each statement using a term or terms from the list below. Write your answers in the spaces
provided. Some words may be used more than once.
all
red
opaque
green
filter
absorbs
reflects
transparent
does not
transmits
1. An object that does not allow light to pass through it is said to be
....__~
2. An object that does allow light to pass through it is said to be
3. The color of an opaque object is the color it
4. A white object reflects
5. A black object
--'-
_
_
_
the colors that make up white light.
reflect light. A black object
all
the light that strikes it.
6. A green sweater absorbs all colors except
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_
7. The color of a transparent object is the color it
8. Window glass transmits
9. A red glass transmits only the color
_
the colors that strike it.
. It __
other colors.
10. A substance that transmits some colors and blocks others is called a
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_____
all