Waves Teaching Slides, 3.3 If you are using the PowerPoint slides, log in to your FOSSweb account on your internet browser. Then, cut and paste these links into your browser. Resources by Investigation provides access to all notebook masters, teacher masters, online activities, and video content: http://www.fossweb.com/resources-by-investigation?folioID=G4335255&parentID=G4324864 The eBook provides access to all FOSS Science Resources articles: http://www.fossweb.com/delegate/ssi-wdf-ucm-webContent/ Contribution%20Folders/FOSS/ebooks_NG/Waves_NG_SRB/Waves_SRB.html If you are using the PDF versions of the slides, simply log in to your FOSSweb account before starting; the embedded links will take you directly to the Resources by Investigation and the eBook. If you plan to use these slides offline, be sure to plan ahead and download the necessary duplication masters from the Resources by Investigation section of FOSSweb. Waves Course, 3.3: Color

Science Log Quarter 4 Week 7  Monday 5/8: What is your favorite color? What is your least favorite color? Waves Course, 3.3: Color

Spectra page 42 Notebook sheet 17, How Do We See? Think about 2 claims and write your initial responses individually. Then, share with your table Waves Course, 3.3: Color Step 1

Discuss sight Discuss your reasoning. What happens in a room that is completely dark? If your eyes are are somehow sending out light waves, how come they do not work in a totally dark room? Waves Course, 3.3: Color Step 2

3. Explore filters Each pair will get 2 filters, Look around the class to see what things look like through the filters What do these color filters do? They let only one color of light pass through. Open your notebooks and make a quick model to explain your idea What needs to be added to the model to show waves reflecting. Waves Course, 3.3: Color

3. Explore filters You know that waves can reflect off surfaces. What our eyes see as color is actually light reflecting off different objects. When you see blue, that is one kind of wave that is reflecting toward your eye. As you learned with the spectroscope, blue light has a specific wavelength. When you see red, that is another kind of wave that is reflecting toward your eye. Red light has a specific wavelength. It’s different from the blue wavelength. Green has its own wavelength, purple has its own wavelength, and so on. Waves Course, 3.3: Color

Explore filters Light waves reflect off the objects that you see. Where do those light waves originate? Whatever light source is present; Sun, ceiling lights, etc. Why can’t you see color in the dark? There are no (or very few) light waves reflecting off surfaces. Waves Course, 3.3: Color Step 3

Focus question 3.3 page 43 What makes objects appear as different colors? Waves Course, 3.3: Color Step 4

Focus the exploration You will look at each color box on the sheet through each color filter to learn more about the properties of light waves. We want to analyze the light reflected by each colored box on the sheet. The original source of the light is the classroom lights, or skylight. When light sources shine on any surface, three things can happen: some colors of light may be absorbed, some may be reflected, and some may pass through. Consider what happens to the light as it hits the boxes on the paper and eventually ends up at your eyes. Waves Course, 3.3: Color

Focus the exploration Waves Course, 3.3: Color Step 5

5. Focus the exploration What does reflect mean, when we are talking about waves? To bounce off What does absorb mean, when we are talking about waves? To take in. Waves Course, 3.3: Color

Describe filter use Waves Course, 3.3: Color Step 6

Analyze color reflection Think about the light waves as you view each box, especially when you view the black and white boxes. You will be able to determine whether the box appears light or dark through each filter and so use this to think about the light reflecting from the box. Waves Course, 3.3: Color

Analyze color reflection page 44 Notebook sheet 18, Color Reflection Observations Color analysis card Record your observations Waves Course, 3.3: Color Step 7

Discuss color reflection Based on your data, what statements can you make about the relationship between the color of the objects and which colors they absorb or reflect? Waves Course, 3.3: Color Steps 8

8. Color reflection notes page 45 Share you ideas and explain your reasoning White objects reflect all colors of light and absorb no colors of light. Reasoning: When we looked at the white box with each color filter, we could see that color. That meant that each wavelength we considered was reflected back from the box. No colors were absorbed. Waves Course, 3.3: Color

8. Color reflection Share you ideas and explain your reasoning Black objects reflect no colors of light and absorb all colors of light. Reasoning: When we looked at the black box with each color filter, we could see no color. That meant that each wavelength we considered was not reflected back from the box. They must have been absorbed. Waves Course, 3.3: Color

8. Color reflection Share you ideas and explain your reasoning An object of a particular color reflects light of that color and absorbs other colors. Reasoning: When we looked at each box with its own color filter, we could see the color, so that color was reflected back from the box. But when we used the other colors, we saw black. Those colors must have been absorbed. Waves Course, 3.3: Color

9. Real-world implications When you look at grass, why do you only see green and not all the other colors of the Sun’s light? The grass surface absorbs certain wavelengths and reflects others. The grass absorbs many wavelengths and reflects green light waves to our eyes. Waves Course, 3.3: Color

9. Real-world implications When you look at something, what color is being reflected to your eye? The color of the object What colors are being absorbed by the object? All other colors/wavelengths of light Objects of different colors reflect certain wavelengths of light (the color they appear) and absorb all other wavelengths. Waves Course, 3.3: Color

10. Objects in the room Look around the room with the filter again Pick an object and describe to a partner The name of the object, Its color, and A description of how it looks through the green filter and through the red filter. Waves Course, 3.3: Color

11. Absorb all light Predict what will happen when you look through both the red and green filters together. Why do the red and green filters together block all light? The red filter absorbs all colors except red, and the green filter absorbs the red light, too. Waves Course, 3.3: Color Step 11

Homework page 46 Notebook sheet 19, Response Sheet—Investigation 3 Waves Course, 3.3: Color Step 12

Homework Notebook sheet 19, Response Sheet—Investigation 3 Draw a line and add: Light waves reflected off an object determine the color of an object. Both wavelength and frequency are properties of light waves that determine color. Waves Course, 3.3: Color Step 12

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