Workshop 3:
Pigments, Paints, and Printing
DESCRIPTION
The colors that surround us provide a rich visual experience. In this workshop we will create rainbows and learn how and why these magnificent phenomena occur in the sky. After looking at the
Sun’s electromagnetic spectrum we will explore the reflection and refraction of photons of light.
We will also examine color televisions and look closely at the pixels which form images, and investigate the primary colors of light and pigments.
LEARNING OBJECTIVES
Participants will be able to:
•
Define color as a characteristic of visible light that depends upon its energy and human perception.
•
Explain that the only thing we see is light that enters the eye.
•
Define what is meant by primary colors.
Workshop 3 timeline
30 minutes
GETTING READY
Thinking about Light and Color
To prepare for today’s workshop, answer the questions below with your discussion group. Create
a chart to record your answers (see sample below).
Question
Our answer prior
to the workshop
Additions to our
pre-workshop
answer
What everyday observations have you
made that indicate to you that white
light is made of different colors?
If white light is made of different colors,
what would be your ‘best guess’ about the
difference among the photons that produce
the different colors in white light?
What does the phrase “primary colors”
mean to you? What makes colors
primary? Are there different colors of
light and of pigment?
A common standard in frameworks
documents states that “the Sun is a source
of heat and light.” If light is photons
(packets of energy), then what do you think
“heat”is and how does it travel from the Sun
to the Earth?
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Workshop 3 timeline
30 minutes
GOING FURTHER
Revisiting “Thinking about Light and Color?”
Return to the questions that we asked your group to answer in Getting Ready. Discuss any
changes that you made (or would like to make) to the pre-workshop ideas.
For Your Journal: A 3-2-1 Summary
In your journal list:
3 — New things that you have learned about light from the series.
2 — Things that you would like to learn more about either because they are interesting or
because they are confusing.
1 — Question that you have about the electromagnetic spectrum
As a group share your questions. Decide on one question and assign a member to post it on the
Web or on channel-talk. You may also want to share your question with your Light Buddy.
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For next time
HOMEWORK ASSIGNMENT
Click on, Click off
Apply the laws of reflection to turn off your television without pointing the remote control directly at the television. To do this you will need to find an object in the room which will reflect the
infrared photons.
X-rays
Knowing how a shadow is made with visible light, think about how X-ray photons can be used to
show details of bones inside of our body. The questions below will guide you in developing your
answer.
•
How are X-ray photons different from visible light photons?
•
What is and is not blocking the path of X-ray photons?
•
What is the surface for an X-ray?
•
How is an X-ray picture like a shadow made with visible light?
•
Why can’t we use visible light photons to see the bones inside of our body?
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Standards
National Science Education Standards
K-4 standards: http://bob.nap.edu/html/nses/html/6c.html#ps
Light travels in a straight line until it strikes an object. Light can be reflected by a mirror,
refracted by a lens, or absorbed by the object.
Content Standards: K-4: Physical Science: Light, Heat, Electricity, and Magnetism
5-8 Standards: http://bob.nap.edu/html/nses/html/6d.html#ps
Light interacts with matter by transmission (including refraction), absorption, or scattering
(including reflection). To see an object, light from that object--emitted by or scattered from
it--must enter the eye.
Content Standards: 5-8: Physical Science: Transfer of Energy
American Association for the Advancement of Science (AAAS) Project 2061 Benchmarks
http://project2061.aaas.org/tools/benchol/bolframe.html
By the end of the 2nd grade, students should be able to:
Raise questions about the world around them and be willing to seek answers to some of them
by making careful observations and trying things out.
Habits of the Mind: 12A Values and Attitudes: K-2
By the end of the 2nd grade, students should know that:
Tools such as thermometers, magnifiers, rulers or balances often give more information about
things than can be obtained by just observing things without their help.
Nature of Science: 1B Scientific Inquiry: K-2
By the end of the 5th grade, students should be able to:
Offer reasons for their findings and consider reasons suggested by others.
Habits of the Mind: 12A Values and Attitudes: 3-5
By the end of the 8th grade, students should know that:
Something can be “seen” when light waves emitted or reflected by it enter the eye—just as
something can be “heard” when sound waves from it enter the ear.
The Physical Setting: 4F Motion: 6-8
Human eyes respond to only a narrow range of wavelengths of electromagnetic radiation—
visible light. Differences of wavelength within that range are perceived as different colors.
The Physical Setting: 4F Motion: 6-8
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Related Sources
Web site: wigner.byu.edu/Colors/TabbedcolorBox.html
This allows you to combine the primary colors of light (R, G, B), but it also allows you to combine pigments (cyan, magenta, yellow) in different proportions to make any possible color.
Feynman, Richard. 1985 QED, The Strange Theory of Light and Matter, Princeton University
Press.
Aldridge, Bill G. 1996. What is Light and How do we Explain it? National Science Teachers
Association, 1840 Wilson Blvd., Arlington, VA 22201-3000, www.hsta.org.
David Falk, Dieter Brill, David Stork. 1986. Seeing the Light: Optics in Nature, Photography,
Color, Vision and Holography. Wiley.
Rossotti, Hazel. 1983. Colour: Why the World Isn’t Gray. Princeton University Press.
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