Download The Colors of Light

Primary Type: Lesson Plan
Status: Published
This is a resource from CPALMS (www.cpalms.org) where all educators go for bright ideas!
Resource ID#: 18944
The Colors of Light
The students will compare/contrast the colors that make up white light in terms of their arrangement in the visible light section of the
electromagnetic spectrum.
Content statements:
White light is made up of all the colors of light and they are organized in the visible light section of the electromagnetic spectrum according to their
wavelengths.
Red has the longest wavelengths and violet has the shortest.
Subject(s): Science
Grade Level(s): 7
Intended Audience: Educators
Instructional Time: 1 Hour(s)
Resource supports reading in content area: Yes
Freely Available: Yes
Keywords: Waves, energy, wavelength, frequency, electromagnetic spectrum, visible light
Resource Collection: iCPALMS
ATTACHMENTS
graphicforSC7P101a.docx
LESSON CONTENT
Lesson Plan Template: Confirmatory or Structured Inquiry
Learning Objectives: What will students know and be able to do as a result of this lesson?
The students will:
Recognize that white light is made up of many different colors of light.
Compare and contrast the colors of visible light in terms of their arrangement in the electromagnetic spectrum.
Content statements:
White light is made up of all the colors of light.
The colors of light in the visible light section of the electromagnetic spectrum are organized according to their wavelengths.
Red has the longest wavelengths and violet has the shortest.
Prior Knowledge: What prior knowledge should students have for this lesson?
SC.7.P.10.1 regarding the electromagnetic spectrum – the different types of waves and their arrangement in the spectrum according to wavelength.
Wavelength, frequency, and energy.
Guiding Questions: What are the guiding questions for this lesson?
What is visible light?
What do you get when you mix all the colors of light?
page 1 of 3 Which color of light has the longest wavelength?
Which color of light has the shortest wavelength?
Introduction: How will the teacher introduce the lesson to the students?
Students are in groups of 3. Each chooses a number – 1, 2, or 3.
Ask: If you mix all the colors of light together, what do you get? Number 3s write down all of the groups’ answers on the white wipe board. Randomly call on students
to share groups’ answers.
Investigate: What question(s) will students be investigating? What process will students follow to collect information that can be
used to answer the question(s)?
Ask: Just after a rain shower (and many times on its leading edge), what phenomenon do we often see in the sky? What is needed for this to occur? Number 3s add
their groups' answers to the white wipe boards.
Students are now to try to make rainbows in the classroom. Give each group a prism and a flashlight. Turn off the lights.
Number 1s are to draw and label a diagram showing what is happening. (They are drawing a model of how a rainbow works). Also, they are to write their groups'
observations on the white wipe boards, answering these questions:
- What is going into the prism?
- What is the order of the colors in the rainbow?
- Which color is at the top of the rainbow and which is at the bottom?
Analyze: How will students organize and interpret the data collected during the investigation?
After all the groups have created rainbows, #2s answer the following questions on the white wipe boards:
In the sky, what is acting like the prism to create the rainbows?
What is the connection between the white light going into the prism and all the colors coming out of it?
Have students look at a diagram of the electromagnetic spectrum, with its different types of waves already labeled. (This diagram could be one they labeled in an
earlier lesson about the electromagnetic spectrum, one in their textbooks, or one you give them).
Based on what is already labeled, in what order would the colors be arranged within the visible light section? Explain your reasoning.
Which color of light has the longest wavelength?
Which color of light has the shortest wavelength?
Randomly call on students to share the groups' answers.
Closure: What will the teacher do to bring the lesson to a close? How will the students make sense of the investigation?
Direct Instruction: The electromagnetic spectrum is the entire range of electromagnetic waves arranged according to their wavelengths. The visible light section is the
only part we can see without the aid of special equipment/technology. Visible light is all of the colors of light arranged in order according to their wavelengths – ROY G
BIV. (The wavelength is what determines what color the light is). Red has the longest wavelength and violet has the shortest. As the white light enters the prism (or
raindrop), it is bent. Because each color has a different wavelength, it is bent at a different angle, causing the colors of light to be separated and form a rainbow.
(Refraction does NOT have to be taught now. Instead, later when it is taught, the prism-rainbow example can be referred to again.)
Also, with this activity, the students separated white light into the colors. Some still may be resistant to the idea that blending the colors of light will produce white.
At this time I recommend using a spinning color wheel to illustrate that the mixing of the colors of light do produce the color white.
Think-Pair-Share:
What is the result if all the colors of light are removed?
Which color has a shorter wavelength – yellow or blue?
If both colors are equally bright, which color has more energy – red or violet?
Feedback to Students
Throughout the activity, the teacher is able to assess student learning by viewing the groups' answers written on their white wipe boards. In addition to answering the
guiding questions and during activity questions, the teacher can ask additional questions based on group responses he/she sees or hears. After the content is
taught/clarified (in Closure), student responses to the Think-Pair-Share questions can also be used for assessment.
ACCOMMODATIONS & RECOMMENDATIONS
Accommodations:
Students with learning needs are working in groups with knowledgeable peers.
Special Materials Needed:
White wipe boards with different colored dry erase markers.
1 flashlight and 1 prism per group.
See the graphics file in the "Uploaded File Attachments" at the end of this lesson plan for:
A blank electromagnetic spectrum diagram that the students can fill out in an earlier lesson.
An electromagnetic spectrum diagram that is labeled except for the order of the colors of light.
In the Closure activity, I mention using a spinning color wheel. I have tried many color wheels (even making my own). If the colors are not just right, when it spins you
page 2 of 3 don't really get white. I finally found one that works very well (showing white) and it is very easy (no power drills needed, etc.). I use the Magic Color Wheel from
Educational Innovations, Inc. http://www.teachersource.com/product/magic-color-wheel/light-mixing
SOURCE AND ACCESS INFORMATION
Contributed by: Lora Lindsey
Name of Author/Source: Lora Lindsey
District/Organization of Contributor(s): Marion
Is this Resource freely Available? Yes
Access Privileges: Public
License: CPALMS License - no distribution - non commercial
Related Standards
Name
SC.7.P.10.1:
Description
Illustrate that the sun's energy arrives as radiation with a wide range of wavelengths, including infrared, visible, and
ultraviolet, and that white light is made up of a spectrum of many different colors.
Related Access Points
Access Point Number
SC.7.P.10.In.1:
SC.7.P.10.Su.1:
Access Point Title
Identify that white (visible) light has many colors, such as when viewed with a prism.
Recognize that white (visible) light contains many colors, such as viewed with a prism or rainbow.
page 3 of 3