Teacher Notes for Light Waves and Color

 

 

 

Unit Overview

We estimate this to be a 11-day unit if you address all the Learning Outcomes. We have alloted time for a mid-unit quiz. An additional day should be added for an exam. There are three primary goals for the unit:
 

1. To understand the concept of wave-particle duality and to be able to offer reasons for why scientists have believed in a particle model and a wave model of light.
2. To describe the trends in wavelength, frequency, and energy for the various regions of the electromagnetic spectrum and for the various colors of the visible light spectrum.
3. To use principles of color addition and color subtraction to explain how the eye sees color.

 

Color!!!

Compared to most other curriculum, The Physics Classroom places a heavy emphasis upon the topic of how our eyes see color. Besides having a personal interest in the topic, we have found that the physics of color is the favorite topic of many students who are exposed to this emphasis. Among the group of enthusiastic students who favor this topic over all others are students who are generally not very interested in Physics. Put another way, the topic of color reaches the most unreached students in our classes. Before making the decision to de-emphasize the topic, consider the students that would be impacted by the de-emphasis. With that being said, if you needed to steal a couple of days from the Light and Color unit for use elsewhere, reducing the number of days spent on Outcomes #5-#7 could provide 2-3 days of time spent for other topics.


 

Labs

We have proposed four labs for this unit. Three of these labs have been used in our other courses; details for those labs are on our Lab Page for this unit.  Lab 3 cannot be found on our site so we have provided further details below.

Lab 1: Lab 1 is identical to a lab that we have used for our other courses. We have provided a link to the Teachers Guide on our Lab Page.

Lab 2: Lab 2 is identical to a lab that we have used for our other courses. We have provided a link to the Teachers Guide on our Lab Page.

Lab 3: This lab requires the use of a bag of multi-colored M&Ms (black, blue, green, red, and yellow work well), sources of red, green, and blue light; a black table or black construction paper, a make-shift cover under which to do the lab while blocking out room lights. For a cover, we have used 2'x2' whiteboards mounted on top of a frame made of 2x4s. (The 2x4s  were our whiteboard stands - wood with a groove cut in them to hold the whiteboards vertically.) Student place the M&M in the darkness of the cover and shine different light colors and combinations of light colors on them one at a time. They record their observations of the color appearance of the M&M for each incident light color.

NOTE: A virtual version of Lab 3 was created during the pandemic and is available in our Interactives section. See Viewed in Another Light. We suggest doing the actual lab as it is much more fascinating (and our photography that the Interactive depends upon is not highly professional).

Lab 4: Lab 4 is identical to a lab that we have used for our other courses. We have provided a link to the Teachers Guide on our Lab Page.

 

Physics Interactives

The Light Waves and Color chapter of our Physics Interactives is packed with simulations. If you haven't looked at this chapter in a few years, it's worth another look. There have been many recent additions.



 

Science Reasoning Center

We have several Light Waves activities at our Science Reasoning Center. These provide a slightly different approach than Concept Builders or Minds On Physics. They tend to emphasize less conceptual development and more scientific processing, data interpretation, experimental analysis, etc. They often make great follow-ups to labs and can sometimes be used as an introduction to a topic. For most topics, they are great accompaniments to an NGSS curriculum. If you have a Task Tracker subscription, visit the Teacher Resources section in order to quickly preview the activity and navigate through all the questions. You will also find information there about NGSS alignments. Here are a few of our favorites:
 

1. Models of Light
   This NGSS-inspired task consists of five activities that probe the dual nature of light. The success and failure of the wave model of light and the particle model of light to explain reflection, diffraction, interference, and the photoelectric effect are explored.
2. Electromagnetic Radiation
   Students compare the relative wavelength, frequency, and energy of the various regions of the electromagnetic spectrum and make the connection of these quantities to the manner in which such waves interact with matter.
3. Light Brightness
   Questions target a student's ability to select data from a table (or two), to interpolate and extrapolate from information given in a table, to draw conclusions consistent with presented information, to identify the relationship among the variables, and to identify statements that are consistent with both the model and the data.
4. Communicating With Electromagnetic Waves
   This NGSS-inspired task includes three parts that focus on the sending, encoding, and storage of information by means of electromagnetic waves.
5. Digitizing Data
   This NGSS-inspired task addresses the manner in which data (such as graphic images) can be digitized and the issues associated with the transmitting, receiving, and storage of digital data.

 

Other Resources

There are a few resources that we did not list in our Lesson Plans and Learning Outcomes and Activities that you may find to be very helpful. These include:
 

1. Concept Builders: Spectrum
   Students seek to understand the ordering of the frequency, wavelength, and energy for the various regions in the continuous spectrum for electromagnetic waves and visible light waves.
2. Concept Builders: If This, Then That - Color Subtraction
   Students use the principle of color subtraction to predict the color of a shirt if given how the shirt appears when viewed under two other colors of light.
3. Minds On Physics, Mission LC3 on Primary Colors of Light
   Students explain the meaning of a primary light color and identify the three primary colors of light AND predict the result of mixing primary colors of light.
4. Minds On Physics, Mission LC6 on Primary Pigments
   Students identify the primary pigments and explain their significance in determining the color which an object will appear AND predict the result of mixing primary pigments.
5. Minds On Physics, Mission LC7 on Pigments and Color Subtraction
   Students predict the color of an object if the pigments imparted to it and the color of light with which it is illuminated are known AND identify the pigments imparted to an object if its appearance under different colored lights is known.
6. Minds On Physics, Mission LC9 on Shadows
   Students use the principles of color addition and subtraction to predict and explain the color of shadows when a combination of light colors are used to create them.
7. Physics Interactives: Electromagnetic Spectrum Infographic
   The Electromagnetic Spectrum Interactive Infographic is full of information about electromagnetic waves. Created in 1944 as a wall-sized poster, this timeless piece of science and art is now available as an interactive app that allows students to tap and explore its many layers of information. Includes a Student Activity Sheet.
8. Physics Interactives: Filtering Away
   Students explore the effect of a filter on various colors of incident light. Includes a Student Activity Sheet and a Concept Checker.
9. Physics Interactives: Colored Filters
   Students learn how various filters interact with various colors of laser light. Once students have figured out the "rules" of how various color filters interact with specific colors of light, they take their understanding a step further by figuring out how color-tinted sunglasses work. Includes a Student Activity Sheet.
10. Physics Interactives: Viewed in Another Light
    So exactly why does a red M&M look red? And does it always look red? Where's the red come from anyways? Students explore these questions and others. Includes a Student Activity Sheet.

 

Teacher Presentation Pack

We probably shouldn't be apologizing for advertising a for-sale item in this space because we have a strong belief that it has a high potential for saving a teacher a lot of time and helping them improve their craft. The item is our Teacher Presentation Pack. It's a well-worth-the-cost tool for any Physics teacher. But for the early-career and cross-over Physics teacher, it's a life saver ... or at least a time saver. It includes a large collection of Slide Decks, Lesson Notes, animations, and graphics for use in your classroom. Once downloaded, you can modify and customize and personalize the contents as needed. You can upload them to your Google Drive and make them available to students. Use the slides as graphic organizers as you prepare students for a Concept Builder or quiz or test. Or use the Slide Decks to organize your presentation of material. We wouldn't be making a big deal about this if we didn't believe it had great value. Learn more here.


 

Also Available ...

Physics teachers may find the following for-sale tools to be useful supplements to our Lesson Plan and Pacing Guide section:

 

1. Task Tracker Subscription (annual purchase)
   A subscription allows teachers to set up classes, add students, customize online assignments, view student progress/scores, and export student scores. Task Tracker accounts allow your students to begin assignments in class or at school and to finish them at home. View our Seat and Cost Calculator for pricing details.
    
2. The Solutions Guide
   We publish a free curriculum with >200 ready-to-use Think Sheets for developing physics concepts. The Solutions Guide is a download containing the source documents, PDFs of source documents, and answers/solutions in MS Word and PDF format. An expanded license agreement is included with the purchase. (Cost: $25 download)
    
3. Teacher Presentation Pack
   This is a large collection of downloadable content packed with nearly 190 Microsoft PowerPoint slide decks, the corresponding Lesson Notes (as PDF and fully-modifiable MS Word format), about 170 animations (in .gif, .png, and .mp4 file formats), a countless number of ready-to-use images (including the original source documents that would allow for easy modification of those images), and a license that allows teachers to modify and use all the content with their classes on password-protected sites (such as course management systems).  (Cost: $40 download)
    
4. Question Bank
   We distribute a Question Bank that includes more than 9300 questions neatly organized according to topic. The Question Bank is the perfect tool for busy teachers or new teachers. Even if you don't use the website with your classes, the Question Bank will assist you in quickly putting together quizzes, tests and other documents with high-quality questions that target student's conceptions of physics principles. And if you do use The Physics Classroom website, the Question Bank is the perfect complement to the materials found at the website. (Cost: $25 download)