Teach 851V Ethan Van Winkle Unit – Optics Overarching Questions How are models helpful at describing phenomena? How much should be trust our observations and intuition? Essential Questions What is light and in what ways can we describe it? Topical Questions How does the human eye, microscope, and telescope work? How does the duality of light impact matter? What are the implications of duality of light? In what ways does light act as a wave and others as a particle? Is light a particle or wave? Standards: Nebraska Science Standards: I. Inquiry: 1. SC 12.1.1.e: Use tools and technology to make detailed qualitative and quantitative observations. (9-12th grade) 2. SC 12.1.1.f: Represent and review collected data in systematic, accurate, and objective manner. (9-12th grade) 3. SC 12.1.1.g: Analyze and interpret data, synthesize ideas, formulate and evaluate models, and clarify concepts and explanations. (9-12th grade) 4. SC 12.1.1.I: Use appropriate mathematics in all aspects of scientific inquiry. (912th grade) II. Science Content: 1. SC12.2.3.a: Describe mechanical wave properties (speed, wavelength, frequency, amplitude) and how waves travel through a medium. (9-12th grade) 2. SC12.2.3.b: Recognize that the energy in waves can be changed into other forms of energy. 3. SC12.2.3.c: Recognize that light can behave as a wave (diffraction and interference) 4. SC8.2.3.c: Recognize that light interacts with matter by transmission (including refraction), absorption or scattering (including reflection). (6-8th grade) Next Generation Science Teacher Standards: 1. HS-PS4-1: Use of mathematical representation to support a claim regarding relationships among the frequency, wavelength, and speed of waves traveling in various media. (9-12th grade) 2. HS-PS4-3: Evaluate the claims, evidence, and reasoning behind the idea that electromagnetic radiation can be either a wave model or particle model, and that for some situations one model is more useful than the other. (9-12th grade) 3. HS-PS4-3: Evaluate the validity and reliability of claims in published materials of the effects that different frequencies of electromagnetic radiation have when absorbed by matter. (912th grade) Unit Map: Monday Intro to Ray Model Three laws of reflection and refraction Geometric Optics – Thin Lenses Converging and Diverging lenses Tuesday Review Three Laws, Discussion about dispersion Lenses Continued, The eye, microscope, telescope Week 3 Physical OpticsPolarization Diffraction Intro to Particle Model of Light – History (photoelectric effect lab/activity) Week 4 Compton Scattering, Rayleigh Scattering Lasers Week 1 Week 2 Wednesday Internal Reflection, and double rainbow Thursday Intro to Geometric Optics – Mirrors Friday Geometric Optics- Lens Lab Introduce/Review to Waves – (talk about sound) Introduction to Wave Model of Light, discussion about real dispersion Spectrum – Continuous, Absorption, Emission Astronomy applications Physical OpticsConstructive and Destructive Interference How is light made Absorption and Emission of Light, (motion of charged particles if EM was discussed) De Broglie particle and wave duality ReviewModels and importance Spectrum – Continuous, Wien displacement law, StefanBoltzmann Astronomy applications Test Ten-Day Plan: Week 1: 1. Monday: Intro to Ray Model - Three laws of reflection and refraction The students will come in and fill out a starter ticket related to light to get them focused on the topic. To introduce the topic of light as a ray, I will use the YouTube video double rainbow to give the students an interesting phenomena and a goal for them to seek to understand how it works. I will be using a simulator called bending light from PHET to allow the students explore the three laws of reflection and refraction. This will be done in small groups with a whole class discussion during specific parts. For more details related to this lesson look at the appendix for the worksheet and full 5E plan. At the end of the class, the students will write in their journals or submit an exit ticket about what they learned and what they still have questions about. Also homework will be assigned. 2. Tuesday: Review Three Laws, Discussion about dispersion and double rainbow continued. The students will come in and fill out a starter ticket related to the three laws learned last class. We will review the laws but this time by doing some problems related to them. These problems will be helpful guides to the homework assigned. Afterwards, we will continue talking about how a double rainbow forms. I will raise the question, how does the different colors come about? We will use the bending light simulator to see how each different color has a different angle coming out of the prism. Then show white light to show that it creates a rainbow effect. I will introduce the term dispersion and comment that we will discuss this topic later on in the unit (can’t describe it using rays). At the end of the class, the students will write in their journals or submit an exit ticket about what they learned and what they still have questions about. 3. Wednesday: Internal Reflection and double rainbow fully explained. The starter ticket for this class will review over dispersion and a problem for covering the laws of reflection. I will have either a demo or video showing internal reflection such as the ones below. I will ask the students to list off observations of what is going on and how we might test it ourselves. Using the simulation “bending light” the students can discover that they can recreate total internal reflection. I will discuss the phenomena and I will introduce multiple applications for this in technology such as optical cables. Then we will work together to understand how internal reflection, dispersion, and the three laws explain the double rainbow phenomena. At the end of the class, the students will write in their journals or submit an exit ticket about what they learned and what they still have questions about. https://www.youtube.com/watch?v=2kBOqfS0nmE https://www.youtube.com/watch?v=s7w1Z1FCgwA 4. Thursday: Intro to Geometric Optics – Mirrors The starter ticket for this class will review over internal reflection and possible applications for it. We will discuss the applications of the information we have learned in the past few classes dealing with mirrors. This will allow me to introduce terminology that can be used for tomorrow’s lab. I will talk about the misconceptions about mirrors regarding the reverse from left to right and the father away you get from a mirror the more you can see of your body. The rest of the period will be related to the students working on their homework or either more materials will be available so that they can do something related to science. At the end of the class, the students will write in their journals or submit an exit ticket about what they learned and what they still have questions about. 5. Friday: Geometric Optics- Lens Lab Every Friday we will have a quiz related to the homework. This will cover the past 4 days of material. After the quiz, there will be a lab dealing with converging and diverging lenses. This allows the students to have a physical connections with the outcomes of the lenses before discussing the topic on Monday of week 2. The details are listed below. At the end of the class, the students will write in their journals or submit an exit ticket about what they learned and what they still have questions about. Lens Lab (General Idea) Question: How would you describe the images formed by a converging and a diverging lens for nearby and distant objects? Purpose: To describe the orientation and relative size of the images produced by a converging and a diverging lens for nearby and distant object locations. A complete lab write-up includes a Title, a Purpose, a Data section, a Conclusion/Discussion. The Data section should document the observations of relative size and orientation in an organized manner; a table would be a wonderful idea. The Conclusion/Discussion should include an organized paragraph in which you respond to the question raised in the Purpose of the lab. Week 2: 6. Monday: Geometric Optics – Thin Lenses (Converging and Diverging lenses) The starter ticket for this class will ask questions related to what the students found in the converging and diverging lenses. When the tickets are discussed, this will be a great way to start introducing terms to the results they have found. The rest of the class will discuss the rules related to lenses and we will start to work on problems related to them. At the end of the class, the students will write in their journals or submit an exit ticket about what they learned and what they still have questions about. Also homework will be assigned. 7. Tuesday: Lenses Continued and expand the eye, microscope, telescope The starter ticket for this class will request the students to draw the rules out for the lenses and an easy problem related to them. We will expand the application of lenses by discussing how the eye, microscope, and telescope work with lenses. At the end of the class, the students will write in their journals or submit an exit ticket about what they learned and what they still have questions about. 8. Wednesday: Introduction or Review of Waves The starter ticket for this class will request the students to draw either a microscope or telescope diagram from last class. I will have slinkys available and I will ask my students to try and create different waves. We will then discuss possible options and narrow it down to two longitudinal and transverse. I will show real world examples of these kinds of waves. Then I will ask the students to list properties of a wave. I will then introduce the math and science terms related to the given properties. At the end of the class, the students will write in their journals or submit an exit ticket about what they learned and what they still have questions about. 9. Thursday: Introduction to Wave Model of Light The starter ticket for this class will request the students to draw a wave and lists its properties. I will start off with a demonstration or video that will show light acting as a wave. I will ask my students to predict the outcome with the knowledge they have learned from the past 2 weeks. They should see that the outcome does not match what a ray would do. I will mention that we will cover the rest of the phenomena during a later date. I will construct how the properties of waves discussed in the last class is related to the characteristics of light. I will compare and contrast sound and light throughout the lesson. I will also discuss how the ray model is a simplification of the wave model. At the end of the class, the students will write in their journals or submit an exit ticket about what they learned and what they still have questions about. 10. Friday: Physical Optics- Constructive and Destructive Interference The quiz will cover the past 4 days of material related to the homework. I will show the video again from last lesson. We can discuss what characteristics of what happened and introduce scientific terms related to the phenomena that was skipped over last time. I will use the PHET simulator Interference and a provided worksheet created by one of the collaborators on the website to have the students investigate the wave properties of water, sound, and light. They ultimately will be able to derive the interference equation for a double slit. At the end of the class, the students will write in their journals or submit an exit ticket about what they learned and what they still have questions about. Two 5E Lesson Plans: Week 1 Monday (worksheet in appendix): Lesson Plan One 1. Grade: 9-12th grade Topic: Introduction to Ray Model of Light (Unit Light) 2. Learning goals: a. Introduction Laws of reflection and refraction. 1. Laws of reflection and refraction ● Incident, reflected, and refracted rays and the normal to the surface all lie in the same place (plane of incidence) ● angle of incidence is equal to angle of reflection (law of reflection) ● law of refraction (Snell’s law) b. This will ultimately lead to of how a double rainbows are formed in further lessons. 3. Next Generation Science Standards and Nebraska Science Standards a. NGSS 1. HS-PS4-1: Use of mathematical representation to support a claim regarding relationships among the frequency, wavelength, and speed of waves traveling in various media. (9-12th grade) 2. HS-PS4-3: Evaluate the claims, evidence, and reasoning behind the idea that electromagnetic radiation can be either a wave model or particle model, and that for some situations one model is more useful than the other. (9-12th grade) b. NSS 1. SC8.2.3.c: Recognize that light interacts with matter by transmission (including refraction), absorption or scattering (including reflection). (68th grade) 2. SC 12.1.1.e: Use tools and technology to make detailed qualitative and quantitative observations. (9-12th grade) 3. SC 12.1.1.f: Represent and review collected data in systematic, accurate, and objective manner. (9-12th grade) 4. SC 12.1.1.g: Analyze and interpret data, synthesize ideas, formulate and evaluate models, and clarify concepts and explanations. (9-12th grade) 5. SC 12.1.1.I: Use appropriate mathematics in all aspects of scientific inquiry. (9-12th grade) 4. Inquiry Instruction a. Engage: https://www.youtube.com/watch?v=OQSNhk5ICTI 1. I will show the famous YouTube video “double rainbow” and pose the question what would we need to know to attack this question. Each table group or shoulder partner will talk to themselves first to discuss possible ideas. They will be provided a worksheet where they can write their answers and why they think they are important. I will then ask each group to submit their ideas. Afterwards, it can be completely open to all students. This will allow me to introduce terms that will make connections to prior knowledge. I will guide the conversation to focus on material and reflection if any tangents come about. The students will be able to write down the class discussion answers in the space provided on the worksheet. (10 minutes) b. Explore: https://phet.colorado.edu/en/simulation/bending-light 1. Using the PHET simulation “Bending Light” we can explore the properties of the physical system. This introduces physical connections with reflection, refraction, and index of refraction of different materials. The worksheet requires them to make a prediction of what they will think will happen when starting the simulation. We will come together as a class and discuss what happened when the laser is turned on. I will introduce normal, incident, and refraction definitions from their descriptions they gave me. Then I will ask my students to look at the “more tools” tab to explore the relationship between velocity and index of refraction (10 minutes). I will ask them what relationship they found and this will allow me derive the equation for index of refraction in the Teacher Guided Explanation. (5-7 minutes) 2. Afterwards, I will have my students explore the “intro” tab using the tools to look at the intensity and angles of the incident, reflection, and refraction rays (10 minutes). I will ask the students their findings and potential relationships. This will allow me to derive and introduce the three laws in the teacher guided explanations part of the worksheet. (10 minutes) c. Explain 1. For student explanation, the worksheet is constructed so that they students make predictions and find out if their predictions match the results. They are asked to draw diagrams or write a sentence of the relationship. I will use these results and student written sentences to construct the laws in the teacher guided explanation sections of the worksheet. 2. For teacher explanation, I have in my worksheet a specific section where I will discuss and elaborate on the results the students find. This will allow me to introduce the three laws and other concepts listed below. ● Using the “more tools” tab, the students will investigate the variables involved in the index of refraction. Their descriptions and with my guidance, the definition of index will be constructed.. ● Using the “intro” tab, the students will investigate the intensity of the light of the three different rays produced. It will show them that nothing is lost and they all add up to 100% (introduces the first law: all in the same plane). ● Using the “intro” tab, the students will investigate the angles of the incident and reflection ray. When looking at the recorded values, they will find that the angles are always the same (introduces the second law). ● Using the “intro” tab, the students will investigate the angles of the incident and refraction rays. I will ask them to plot the cosine and sine of the angles. They will come across a linear relationship for the sine. The slope will be the index of water. This will derive Snell’s law (third law). d. Elaborate 1. How these ideas can be applied to the double rainbow. 2. The simulation “bending light” in the all three tabs have mystery objects that the n value can be found. So if there is time, the students can solve the mystery index value. e. Evaluate 1. I have constructed a worksheet that shows their active participation when doing the activity. It will show me their reasoning skills from their predictions to writing out relationships. 2. In the last part of the worksheet, it will target elaborating on the past knowledge by solving a mystery index of refraction object and explaining how this new knowledge can be applied to a double rainbow. 3. Otherwise, I will be constantly evaluate throughout the lesson and see where more guidance needs to be added. 5. Address ELL students a. I am asking the students to describe to me what they see with their own prior knowledge when they investigate and observe the simulations. This will allow them to make connections with the scientific names when I introduce them. 6. Address special needs a. As the students are investigating the simulations and variables, I will be walking around assisting when guidance is needed. This will help the students that need more help compared to the ones that will be fine without it. The worksheet I have constructed has some guidance to the lesson but still enough inquiry. Even if the students get lost, we will be meeting up every 10 minutes to discuss the findings and relationships as a class. I will also provide my own instruction in the guided explanation sections. 7. Address equal participation a. When discussing on how to attack the problem for the double rainbow, I allow the students to talk in groups or partners. This will allow them to feel more comfortable when the discussion is opened up. b. When the students are investigating the variables for each part of the simulator, I will ask one be the data recorder and the other use the simulation. When another relationship is looked into, I will ask them to switch roles. Week 1 Wednesday (worksheet in appendix): Lesson Plan Two th Grade level: 9-12 Topic: Internal Reflection and Double Rainbow Learning Goals: The derivation of internal reflection and applications of it. How single and double rainbows are formed using dispersion, laws of reflection and refraction, and internal reflection. Next Generation Science Standards addressed: 1. HS-PS4-1: Use of mathematical representation to support a claim regarding relationships among the frequency, wavelength, and speed of waves traveling in various media. (9-12th grade) 2. HS-PS4-3: Evaluate the claims, evidence, and reasoning behind the idea that electromagnetic radiation can be either a wave model or particle model, and that for some situations one model is more useful than the other. (9-12th grade) Nebraska State Science Education Standards (2010) addressed: I. II. Inquiry: 1. SC 12.1.1.e: Use tools and technology to make detailed qualitative and quantitative observations. (9-12th grade) 2. SC 12.1.1.f: Represent and review collected data in systematic, accurate, and objective manner. (9-12th grade) 3. SC 12.1.1.g: Analyze and interpret data, synthesize ideas, formulate and evaluate models, and clarify concepts and explanations. (9-12th grade) 4. SC 12.1.1.I: Use appropriate mathematics in all aspects of scientific inquiry. (912th grade) Science Content: 1. SC12.2.3.a: Describe mechanical wave properties (speed, wavelength, frequency, amplitude) and how waves travel through a medium. (9-12th grade) 2. SC8.2.3.c: Recognize that light interacts with matter by transmission (including refraction), absorption or scattering (including reflection). (6-8th grade) Reference the source of all activities (title, author, year): Total Internal Reflection worksheet, Shawn Templin, 2014 Materials for activity: optical cables if not showing video demonstrations Instructional & Assessment Plan Inquiry Phase Instructional Activity & Evaluation Tool How long? Engage I will show the video 10 minutes including the videos. https://www.youtube.com/watch?v=s7w1Z1F CgwA demonstrating internal reflection. This video shows water fall out with the light trapped inside the falling water. I will have my students write down what they observe. I will follow up with another video displaying a better view https://www.youtube.com/watch?v=2kBOqfS 0nmE. This video shows internal reflection with multiple different colors and different angles. I will have the students discuss what they see in groups and how they will recreate this phenomena. They should make a prediction of what needs to happen from the videos. Explore The students will use the “Bending Light” 15 minutes simulator from PHET to try and recreate the internal reflection. The students will have a guided worksheet to help introduce the idea to internal reflection. Explain (Part 1: Students) I will ask the students to explain their findings 5-10 minutes in a class discussion. Explain (Part 2: Teacher) Using their findings, I can derive or elaborate on the idea of internal reflection. 5-10 minutes Elaborate I will discuss the applications of internal reflection such as optical fibers. They have higher data rate, safer, clearer signal, etc. I The remainder of the class. The rainbow explanation might will then have the students in groups predict on how they think rainbows are formed. I will ask around what predictions the students have come to and I will continue to discuss how rainbow and double rainbow are formed. continue to the next day since the explanation is difficult and long. Assessment: 1. The worksheet will show their active participation when doing the activity. It will also show their reasoning and mathematical skills. Addressing ELL students: 1. I am asking the students to describe what they see using their own prior knowledge when they observe the videos displaying internal reflection. This will allow them to make connections with the scientific names when I introduce them. Doing the worksheet will also give them different perspectives on how internal reflection is described. Addressing special needs students: 1. As the students are investigating the simulations and variables, I will be walking around assisting when guidance is needed. This will help the students that need more help compared to the ones that will be fine without it. Also the worksheet given has some guidance to the lesson. Even if the students get lost, we will be meeting up at the end as a class to discuss the findings and relationships. Addressing equal participation: 1. When viewing the videos, I will be asking the students to discuss what they see in groups so that they can catch all the details. I will then ask them to collaborate on what they think needs to happen to recreate the phenomena observed. 2. After the investigation, I will ask the groups what their findings are and what relationships they found. 3. I will have the students in groups discuss how they think a rainbow is formed and we will go around seeing what people think happens. I will then derive and explain rainbows. Assessments: Formative: 1. Daily Start Tickets: This is to give students to do something while the class is starting. It will ease their mindset into thinking science. The answers will be discussed shortly after class starts, it will be used for roll call. 2. Lab Activity Worksheets: During lab days, students will either have worksheets or selfcreated papers that will be turned in. This helps guide and construct their ideas while also extending their knowledge. 3. Daily Journals/Exit Tickets: Students will fill out at the end of class something they learned that day and something they still don’t understand. Cumulative: 1. Weekly Quizzes: The quiz is based on the weekly homework assigned. The problems are nearly identical to the given homework and notes are allowed to be used. This will incentivize the students to do the homework while not requiring me to grade every problem they have been assigned for the assignment. 2. End of Unit Exam Appendix: NAME:____________________ Light as a Ray Double Rainbow 1. What do we need to know to understand this phenomena? List possible ideas and explain why they would be appropriate to try to figure out the event. 2. Class Suggestions: Bending Light Simulator (make sure you have the ray laser view selected) 3. Make and write a prediction with a diagram of what you think will happen when you turn on the laser. 4. Did your prediction match the outcome? If not, draw the result below. 5. Select the tab “More Tools” at the top of the simulator. Explore what the relationship between velocity and index of refraction. Make and write out a prediction before making any measurements. (Use the Speed tool in the tool box) 6. Did your prediction match the results measured? Construct a sentence that describes the relationship between velocity and index of refraction. Teacher Guided Explanation: 7. Select the tab “Intro” and look at the intensity of the three different rays. Make a prediction before making any measurements. Construct a sentence that describes the relationship between the three rays. Teacher Guided Explanation: 8. In the “Intro” tab, explore the relationship between the incident ray angle and reflected ray angle. Before making any measurements make and write down a prediction. (Use the protractor in the tool box) 9. Did your prediction match the results measured? Construct a sentence describing the relationship between the two different angles. Teacher Guided Explanation: 10. In the “Intro” tab, explore the relationship between the incidence and refracted angles. 11. In excel, convert your angles into radians. Then compare COS vs COS and SIN vs SIN in excel. Make sure that incident is on the y-axis and the refracted is on the x-axis. Then add a trendline to show the equation. What conclusions can be made when looking at the two graphs? Teacher Guided Explanation: 12. In either in the “Intro” or “More Tools” tab, select mystery material A or B for the bottom medium and solve for the index of refraction. 13. Using the three laws of reflection and refraction, how might these laws help understand the double rainbow phenomena? Name: __________________________ Date: ___ / ___ / ___ Total Internal Reflection Setup: Head to the website http://phet.colorado.edu/en/simulation/bending-light and download the simulation. When it opens, change the Laser View to ‘Ray’ and you’ll be all set up. Part 1: Total Internal Reflection As light travels from one material to another there is often refraction and reflection. There are some points, however, where the beam is totally reflected. We call this phenomenon total internal reflection. Experiment with the simulation until you get a ray of light that achieves total internal reflection. You can switch the materials around using the tool box on the right-hand side. What were your first and second materials in this case? ______________________________________________________________________________ ____________________ Using the protractor, measure your angles of incidence and reflection. Remember, all angles are measured from the normal. 𝜃𝑖 = _______ 𝜃𝑟 = _______ Can you achieve total internal reflection when light is trying to travel from glass to air? ______________________________ Can you achieve total internal reflection when light is trying to travel from air to glass? ______________________________ Can you achieve total internal reflection when light is trying to travel from water to air? ______________________________ Can you achieve total internal reflection when light is trying to travel from air to water? ______________________________ Can you achieve total internal reflection when light is trying to travel from glass to water? ____________________________ Can you achieve total internal reflection when light is trying to travel from water to glass? ____________________________ Based on the 6 previous scenarios, in which of the following illustrations could you possibly get total internal reflection? Part 2: The Critical Angle The critical angle is the angle of incidence that provides an angle of refraction of 90-degrees. It is the very first point where you get total internal reflection. Using the Protractor, determine the critical angle of the following interfaces: Glass to Air: _________ Water to Air: _________ Glass to Water: _______ Using Snell’s Law you can solve for an expression for the critical angle, 𝜃𝐶 . I’ll get you started with the first two steps. Finish the rest to solve for 𝜃𝐶 . 𝑛1 𝑠𝑖𝑛𝜃1 = 𝑛2 𝑠𝑖𝑛𝜃2 𝑛1 𝑠𝑖𝑛𝜃𝐶 = 𝑛2 sin(90°) θ𝐶 = Using your new expression for the critical angle, determine the critical angles for the following interfaces. Show your work below. Glass to Air Water to Air Glass to Water Do these results confirm the critical angles you calculated with the protractor?