9P.2.3.3 Light & Optics
Describe the nature of the magnetic and electric fields in a propagating electromagnetic wave.
Explain and calculate how the speed of light and its wavelength change when the medium changes.
Explain the refraction and/or total internal reflection of light in transparent media, such as lenses and optical fibers.
Use properties of light, including reflection, refraction, interference, Doppler effect and the photoelectric effect, to explain phenomena and describe applications.
Compare the wave model and particle model in explaining properties of light.
Compare the wavelength, frequency and energy of waves in different regions of the electromagnetic spectrum and describe their applications.
Overview
MN Standard in Lay Terms
The behavior and properties of electromagnetic energy should be modeled showing both aspects of the wave/particle understanding. The velocity or propagation of this energy is a constant maximum value c in free space and the direction of its path follows that of free space until encountering a medium. Surfaces that interact with the energy will reflect and/or refract the wave/particle energy according to observed laws of reflection and refraction. The electromagnetic energy can interact with openings and objects producing observable diffraction and interference effects generally associated with other forms of waves. Some surfaces will absorb the wave/particle energy and eject electrons based on the rules governing the photoelectric effect and Plank's Law in a manner suggesting particle like energy transfer. Students should understand that everything from the images they see of themselves in the mirror, the transmission of their text messages on cell phones, changing the channel with a remote control, the color of a rainbow or soap bubble, awe-inspiring images of distant objects in the universe, and the images of broken bones by X-ray are all related to our understanding of the behavior of electromagnetic radiation.
Big Idea
Any electric charge which accelerates, or any changing magnetic field, produces electromagnetic radiation. (9P.2.3.3.1)
When an electromagnetic wave changes speed at the boundary between two media with differing indices of refraction, the frequency of the wave remains constant but the wavelength will vary according to v1/v2=λ1/λ2 or n2/n1=λ1/λ2. (9P.2.3.3.2)
The use of Ray Diagrams and the conceptual understanding of refraction should be developed so students can predict the path of light through various refractive media. Snell's law should be used for quantitative calculations and for the prediction of the conditions for total internal reflection to occur. (9P.2.3.3.3)
Light rays reflect off of mirrored surfaces at equal angles to a normal line drawn to that surface. Ray diagrams tracing these paths can and should be used to predict the image locations for objects at various locations in front of flat and curved mirror surfaces. Use of the mirror equations can predict these locations mathematically. (9P.2.3.3.4)
Light rays refract when passing from one refractive media into another. Ray diagrams tracing these paths can and should be used to predict image locations for objects at various locations front of and behind refractive boundaries such as glass blocks and lenses. Using Snell's Law and the Lens equations properties of the images can be calculated. (9P.2.3.3.4)
Students should understand that a dual model system helps explain the behavior of light. A particle model is useful for explaining aspects such as reflection, some aspects of refraction (ray diagrams), but a wave model work best to explain the variation of wavelength at boundaries for refractive media and for interference and diffraction phenomenon. The particle model is needed again to account for the interaction of light in the photoelectric effect. (9P.2.3.3.5)
Compare and rank the wavelength and frequencies for the Radio, Microwave, Infrared, Visible, Ultraviolet, X-ray, and Gamma ray regions of the Electromagnetic Spectrum. They should understand that no mechanical medium is need to transmit these waves and that they all travel with the same speed c in the free space of the universe. These waves do change speed when traveling through various media but travel again at the speed c when reentering free space. Radars, household device remotes, cell phones, microscopes, etc all make use of different regions of the electromagnetic spectrum. (9P.2.3.3.6)
MN Standard Benchmarks
9P.2.3.3.1 Describe the nature of the magnetic and electric fields in a propagating electromagnetic wave.
9P.2.3.3.2 Explain and calculate how the speed of light and its wavelength change when the medium changes.
9P.2.3.3.3 Explain the refraction and/or total internal reflection of light in transparent media, such as lenses and optical fibers.
9P.2.3.3.4 Use properties of light, including reflection, refraction, interference, Doppler effect and the photoelectric effect, to explain phenomena and describe applications.
9P.2.3.3.5 Compare the wave model and particle model in explaining properties of light.
9P.2.3.3.6 Compare the wavelength, frequency and energy of waves in different regions of the electromagnetic spectrum and describe their applications.
The Essentials
This file is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license.
Two soap bubbles, illustrating iridescent colours, against a foliage background. Photograph taken at Traquair House, Scotland on the 1st August 2003 by BDB. Source: english wikipedia, original upload 3 August 2004 by en:User:Tagishsimon
My Photo use at will (Mike Maas)
1) NSES Standards:
2) AAAS Benchmarks of Science Literacy and Atlas:
from Benchmarks Online - Project 2061 - AAAS (Physical Setting) Benchmarks
Energy Transformations (4E):
4E/H9 - Many forms of energy can be considered to be either kinetic energy, which is the energy of motion, or potential energy, which depends on the separation between mutually attracting or repelling objects.
4E/H10 - If no energy is transferred into or out of a system, the total energy of all the different forms in the system will not change, no matter what gradual or violent changes actually occur within the system.
Motion (4F):
4F/H3a - When electrically charged objects undergo a change in motion, they produce electromagnetic waves around them.
4F/H3c - In empty space, all electromagnetic waves move at the same speed-the "speed of light."
4F/H5ab - The observed wavelength of a wave depends upon the relative motion of the source and the observer. If either is moving toward the other, the observed wavelength is shorter; if either is moving away, the wavelength is longer.
4F/h5c - Because the light seen from almost all distant galaxies has longer wavelengths than comparable light here on Earth, astronomers believe that the whole universe is expanding.
4F/H6ab - Waves can superpose on one another, bend around corners, reflect off surfaces, be absorbed by materials they enter, and change direction when entering a new material. All these effects vary with wavelength.
4F/H6c - The energy of waves (like any form of energy) can be changed into other forms of energy.
Forces of Nature (4G):
4G/H5ab - Magnetic forces are very closely related to electric forces and are thought of as different aspects of a single electromagnetic force. Moving electrically charged objects produces magnetic forces and moving magnets produces electric forces.
4G/H5c - The interplay of electric and magnetic forces is the basis for many modern technologies, including electric motors, generators, and devices that produce or receive electromagnetic waves.
NAEP
Science Framework for the 2009 National Assessment of Educational Progress, U.S. Department of Education, 2009.
See this page.
Forms of Energy:; nuclear energy and waves
P12.10: Electromagnetic waves are produced by changing the motion of charges or by changing magnetic fields. The energy of electromagnetic waves is transferred to matter in packets. The energy content of the packets is directly proportional to the frequency of the electromagnetic waves. (9P.2.3.3.1) (9P.2.3.3.6) |
Common Core Standards
Math standards
(8.1.1.5) Express approximations of very large and very small numbers using scientific notation; understand how calculators display numbers in scientific notation. Multiply and divide numbers expressed in scientific notation, express the answer in scientific notation, using the correct number of significant digits when physical measurements are involved.
For example: (4.2×104)×(8.25×103) =3.465×108 , but if these numbers represent physical measurements, the answer should be expressed as 3.5×108 because the first factor, 4.2×104 , only has two significant digits.
(9.2.1.4) Obtain information and draw conclusions from graphs of functions and other relations.
Students can plot data of incident light angle and refracted light angle through a glass plate to determine the relation for Snell's law.
(9.2.2.1) Represent and solve problems in various contexts using linear and quadratic functions.
(9.2.2.3) Sketch graphs of linear, quadratic and exponential functions, and translate between graphs, tables and symbolic representations. Know how to use graphing technology to graph these functions.
(9.3.1.3) Understand that quantities associated with physical measurements must be assigned units; apply such units correctly in expressions, equations and problem solutions that involve measurements; and convert between measurement systems.
For example: 60 miles/hour = 60 miles/hour × 5280 feet/mile × 1 hour/3600 seconds = 88 feet/second.
(9.3.1.5) Make reasonable estimates and judgments about the accuracy of values resulting from calculations involving measurements.
For example: Suppose the sides of a rectangle are measured to the nearest tenth of a centimeter at 2.6 cm and 9.8 cm. Because of measurement errors, the width could be as small as 2.55 cm or as large as 2.65 cm, with similar errors for the height. These errors affect calculations. For instance, the actual area of the rectangle could be smaller than 25 cm2 or larger than 26 cm2, even though 2.6 × 9.8 = 25.48.
(9.4.1.3) Use scatterplots to analyze patterns and describe relationships between two variables. Using technology, determine regression lines (line of best fit) and correlation coefficients; use regression lines to make predictions and correlation coefficients to assess the reliability of those predictions.
(9.4.2.3) Design simple experiments and explain the impact of sampling methods, bias and the phrasing of questions asked during data collection.
2010 Minnesota Academic Standards - English Language Arts K-12
Curriculum and Assessment Alignment Form
Grades 11-12 Literacy in Science and Technical Subjects
Minnesota Academic Standards: Language Arts
Anchor Standard | Benchmark |
1. Read closely to determine what the text says explicitly and to make logical inferences from it; cite specific textual evidence when writing or speaking to support conclusions drawn from the text. | 1. Cite specific textual evidence to support analysis of science and technical texts, attending to important distinctions the author makes and to any gaps or inconsistencies in the account. |
2. Determine central ideas or themes of a text and analyze their development; summarize the key supporting details and ideas. | 2. Determine the central ideas or conclusions of a text; summarize complex concepts, processes, or information presented in a text by paraphrasing them in simpler but still accurate terms. |
3. Analyze how and why individuals, events, and ideas develop and interact over the course of a text. | 3. Follow precisely a complex multistep procedure when carrying out experiments, designing solutions, taking measurements, or performing technical tasks; analyze the specific results based on explanations in the text. |
4. Interpret words and phrases as they are used in a text, including determining technical, connotative, and figurative meanings, and analyze how specific word choices shape meaning or tone. | 4. Determine the meaning of symbols, equations, graphical representations, tabular representations, key terms, and other domain-specific words and phrases as they are used in a specific scientific or technical context relevant to grades 11-12 texts and topics. |
5. Analyze the structure of texts, including how specific sentences, paragraphs, and larger portions of the text (e.g., a section, chapter, scene, or stanza) relate to each other and the whole. | 5. Analyze how the text structures information or ideas into categories or hierarchies, demonstrating understanding of the information or ideas. |
6. Assess how point of view or purpose shapes the content and style of a text. | 6. Analyze the author's purpose in describing phenomena, providing an explanation, describing a procedure, or discussing/reporting an experiment in a text, identifying important issues and questions that remain unresolved. |
7. Integrate and evaluate content presented in diverse media and formats, including visually and quantitatively, as well as in words. | 7. Integrate and evaluate multiple sources of information presented in diverse formats and media (e.g., quantitative data, video, multimedia) in order to address a question or solve a problem. |
8. Delineate and evaluate the argument and specific claims in a text, including the validity of the reasoning as well as the relevance and sufficiency of the evidence. | 8. Evaluate the hypotheses, data, analysis, and conclusions in a science or technical text, verifying the data when possible and corroborating or challenging conclusions with other sources of information. |
9. Analyze how two or more texts address similar themes or topics in order to build knowledge or to compare the approaches the authors take. | 9. Synthesize information from a range of sources (e.g., texts, experiments, simulations) into a coherent understanding of a process, phenomenon, or concept, resolving conflicting information when possible. |
10. Read and comprehend complex literary and informational texts independently and proficiently. | 10. By the end of grade 12, read and comprehend science/technical texts in the grades 11-12 text complexity band independently and proficiently. |
Misconceptions
1. Gamma rays, X-rays, ultraviolet light, visible light, infrared light, microwaves, and radio waves are all very different entities. (9P.2.3.3.1)
2. Colors appearing on soap films and oil slicks are reflections of rainbows. (9P.2.3.3.4)
3. Light always passes straight through transparent material (without changing direction). (9P.2.3.3.3)
4. When an object is viewed through a transparent material, the object is seen exactly where it is located. (9P.2.3.3.3)
5. White light is pure and colorless light. (9P.2.3.3.6)
6. A prism or colored filter puts color into light when it passes through it. (9P.2.3.3.2,9P.2.3.3.3,9P.2.3.3.4)
7. The speed of light never changes. (9P.2.3.3.2)
8. Refraction is the bending of waves. (9P.2.3.3.3)
9. Light is a mixture of particles and waves. (9P.2.3.3.5)
10. Waves transport matter. (9P.2.3.3.1)
11. There must be a medium for a wave to travel through. (9P.2.3.3.1)
12. Light is one or the other--a particle or a wave--only. (9P.2.3.3.5)
13. Light can be a particle at one point in time and a wave at another point in time. (9P.2.3.3.5)
14. Photons of higher frequency are bigger than photons of lower frequency. (9P.2.3.3.5)
15. All photons have the same energy. (9P.2.3.3.5)
16. Intensity means that the amplitude of a photon is bigger. (9P.2.3.3.5)
Vignette
A Conceptual Introduction to Refraction
Mr. Lumens begins his lesson by giving each pair of students a glass or plexiglass block roughly 4"x6"x1/2" and asked to look at the middle of their upright index finger through the ½ inch side of the glass.
(image of my finger use at will, Mike Maas)
As the block is rotated the middle part of the finger seems to separated and be cut apart from the rest! How can this be happening? The light coming from their finger appears to be coming from a place the finger isn't? Somehow the path of the light has been changed and redirected. The students draw possible pathways that the light may be taking on whiteboards and share their ideas with the class. Other images of refraction are explored and discussed at The Physics Classroom's Photo Gallery.
Mr. Lumens' then demonstrates a laser beam illuminated with chalk dust, canned fog, or smoke as it enters from the air into an aquarium filled with water and a touch of powdered coffee creamer. The students can readily observe that the light beam changes directions at the boundary between the two media. The instructor leads the class in through observations as the laser is moved at differing angles.
Next the students are led back to the lab where each lab group traces the ray created by an inexpensive laser level it is passed through various shapes, (rectangles, prisms, semi circles, circles, concave and convex lens cross sections) of glass or plexi-glass laid on paper. (see photo below)
(my image use at will, Mike Maas)
The instructor helps develop the idea of the ray bending toward or away from the normal line with the lab groups. The next day students are led through a discussion about how the bending of the rays at a surface may be quantified and studied given semicircular dishes filled with a liquid. The students investigate and and work to develop Snell's Law by laboratory work..
The same type of conceptual development may be done with the laser levels and mirrored shapes for reflection.
(my image use at will, Mike Maas)
The Physics of Optics (9P.2.3.3.4)
This instructional video meant for teachers is a wonderful example of lessons and methods related to the teaching of optics. Watch this to get a good feel for what your class may look like while teaching lessons in optics.
An 11th- and 12th-grade physics class looks at light, lenses, and the human eye.
See this page.
Resources
Suggested Labs and Activities
The Physics Front Optics Resources
The Physics Front provides high quality resources for the teaching of physics and physical sciences courses.The Physics Front is a free service provided by the American Association of Physics Teachers in partnership with the NSF/NSDL.
A nice selection of optics related activities with photos of the set up.
See this page. (9P.2.3.3.3)
Vernier Investigations:
Vernier technology is a source of data collection that allows students to accurately predict and analysis data. The links below are the complete labs as posted by Vernier Software and Technology.
Light, Brightness and Distance (9P.2.3.3.1) - Determine the mathematical relationship between intensity and the distance from the light source.
Polarization of Light (9P.2.3.3.5) - Observe the change in light intensity of light passing through crossed polarizing filters. Measure the transmission of light through two polarizing filters as a function of the angle between their axes and compare it to Malus's law.
Reflectivity of Light (9P.2.3.3.4) - Use a computer-interfaced Light Sensor to measure reflected light and calculate percent reflectivity of various colors.
Snell's Law of Refraction (9P.2.3.3.3) - Use Snell's Law to determine the speed of light in Acrylite.
Pasco "Explorations in Physics"
Activity 34 - Inverse Square Law-Light Intensity versus Distance (9P.2.3.3.1)
PDF (2.2 MB) Investigate the relationship between the intensity of light from a small light source and the distance from the source.
Activity 35 - Polarization (9P.2.3.3.5)
PDF (1.1 MB) Investigate how the intensity of light from a small light source changes as it passes through a single polarizer, and how it changes when it passes through two polarizers.
PASCO "Physics with the Xplorer GLX"
Activity 34 - Inverse Square Law-Light Intensity versus Distance (9P.2.3.3.1)
PDF (2.2 MB) Investigate the relationship between the intensity of light from a small light source and the distance from the source.
Activity 35 - Polarization (9P.2.3.3.5)
PDF (1.1 MB) Investigate how the intensity of light from a small light source changes as it passes through a single polarizer, and how it changes when it passes through two polarizers.
Student Practicum Problems:
Practicums For Physics Teachers (Ryan, Henry and Barber, Jon, 2008)
Two high school teachers developed practicums for students to solve problems using an understanding of physics concepts and critical thinking skills. The link below does not get you to the activity, only an order form for the book. This is the only way of purchasing these practicums.
See this page.
Image With a Mirror (p. 10) (9P.2.3.3.4) - With the object filament at a given distance from a concave mirror, place a screen to produce a focused real image. Predict the size of the image.
Image With a Lens (p. 12) (9P.2.3.3.4) - Given an object at a given distance from a convex lens, place a screen to produce a focused real image. Predict the size of the image.
It Is Critical (p. 17) (9P.2.3.3.3) - Determine the depth of a light bulb under water by observing the circle of light produced on the water surface.
Relative Index of Refraction (p. 19) (9P.2.3.3.2) - Place a small paper target on the opposite side of an apparatus from the light sources (laser) in such a way as to catch the beam after it has passed through two different refracting mediums.
Interference Call (p. 21) (9P.2.3.3.4) - Given a HeNe laser and a double slit slide predict the distance from the center to an interference pattern produced by passing through the slide.
Instructional suggestions/options
Videos to learn how to implement the National Standards using Inquiry Techniques from the Annenburg Foundation
To be viewed together at this page.
1. Introduction
Classroom footage and new footage of scientists in the field explain and illustrate the concept of inquiry.
An 11th- and 12th-grade physics class looks at light, lenses, and the human eye.
See Technology Connections: University of Colorado PhET Simulations
Additional resources
NASA's Cool Cosmos Infrared Astronomy Site (9P.2.3.3.1,9P.2.3.3.6)
Communicating the world of infrared astronomy to the public is the main topic of the "Cool Cosmos" portal but certainly not its only goal. In the past few years the "Cool Cosmos" team has created a wide variety of educational products that explain the infrared as well as the multi-wavelength universe. We've produced a suite of award-winning websites (coolcosmos.ipac.caltech.edu) that speak to audiences as varied as kindergarteners to amateur astronomers. We've also filmed short videos about astronomy and infrared light and created posters and brochures that have become favorites with NASA education specialists as well as classroom teachers.
Resource for both teachers and students. Website is sectioned into Read/Watch/Interact, Practice/Review, and Teacher Tools.
Readings at The Physics Classroom
(9P.2.3.3.1,9P.2.3.3.4,9P.2.3.3.6)
The behavior of light waves is introduced and discussed; polarization, color, diffraction and interference are introduced as supporting evidence of the wave nature of light. Color perception is discussed in detail.
Reflection and the Ray Model of Light
(9P.2.3.3.4)
The ray nature of light is used to explain how light reflects off of planar and curved surfaces to produce both real and virtual images; the nature of the images produced by plane mirrors, concave mirrors, and convex mirrors is thoroughly illustrated.
Refraction and the Ray Model of Light
(9P.2.3.3.3,9P.2.3.3.4)
The ray nature of light is used to explain how light refracts at planar and curved surfaces; Snell's law and refraction principles are used to explain a variety of real-world phenomena; refraction principles are combined with ray diagrams to explain why lenses produce images of objects.
Multimedia at The Physics Classroom
Ray Optics Help with drawing ray diagrams for mirrors and lenses. (9P.2.3.3.3,9P.2.3.3.4)
(9P.2.3.3.3)
Use a lifeguard-swimmer analogy to explore the relationship between the speed of a wave in two different media and the angles of incidence and refraction for the wave as it crosses the boundary between the media.
(9P.2.3.3.3)
Investigate the reflection and refraction of light at a boundary. Alter the indices of refraction for the two media and change the angle of incidence. Explore Snell's law of refraction and total internal reflection.
(9P.2.3.3.3)
Investigate how the image characteristics for a lens depend upon the object's distance from the lens. Drag the object to different locations and view the appearance of the image. Change the focal length, the object distance and the object height and observe the effect upon the characteristics of the image. Use the option of showing three principal rays from the extremity of the object.
A simulation to follow up on a real lab or to practice post lab understanding of Thomas Young's double slit experiment. (9P.2.3.3.4)
Review Multiple Choice Questions At the Physics Classroom
(9P.2.3.3.1,9P.2.3.3.4,9P.2.3.3.6)
Description: Questions pertain to the wave properties of light - particularly polarization and two-point source interference. Principles of color addition and color subtraction are used to explain the world of color. The following concepts are emphasized: light as an electromagnetic wave, electromagnetic spectrum, visible light spectrum, polarization, interference, two-point source interference, Young's equation, Young's experiment, wavelength measurement, polarization, color, rods and cones of the eye, primary colors of light, secondary colors of light, primary pigments, secondary pigments, color addition, color subtraction, diffraction and scattering.
(9P.2.3.3.2,9P.2.3.3.3,9P.2.3.3.4)
Description: Questions pertain to light refraction, total internal reflection and image formation by lenses. Snell's law is used to analyze the refraction of light at the boundary between two transparent materials. Ray diagrams and the lens equation are used to analyze the object-image relationships for converging and diverging lenses. The following concepts are emphasized: refraction, Snell's law, angle of incidence, angle of refraction, least time principle, boundary behavior, total internal reflection, critical angle, lenses, diverging lenses, converging lenses, focal point, real versus virtual images, inverted versus upright images, lens equation, and magnification equation.
(9P.2.3.3.3,9P.2.3.3.4)
Description: Questions pertain to light refraction, total internal reflection and image formation by lenses. Snell's law is used to analyze the refraction of light at the boundary between two transparent materials. Ray diagrams and the lens equation are used to analyze the object-image relationships for converging and diverging lenses. The following concepts are emphasized: refraction, Snell's law, angle of incidence, angle of refraction, least time principle, boundary behavior, total internal reflection, critical angle, lenses, diverging lenses, converging lenses, focal point, real versus virtual images, inverted versus upright images, lens equation, and magnification equation.
Photo Images at The Physics Classroom
Light and Color (9P.2.3.3.1,9P.2.3.3.6)
Reflection and the Ray Model of Light (9P.2.3.3.4)
Refraction and the Ray Model of Light (9P.2.3.3.2,9P.2.3.3.3,9P.2.3.3.4)
123Physics: Regents Review Questions, Physics Lessons, Videos, and Physics Clipart
ComPADRE is filling a stewardship role within the National Science Digital Library for the educational resources used by broad communities in physics and astronomy. This partnership of the American Association of Physics Teachers (AAPT), the American Astronomical Society (AAS), the American Institute of Physics/Society of Physics Students (AIP/SPS), and the American Physical Society (APS) helps teachers and learners find, and use, high quality resources through collections and services tailored to their specific needs.
The Physics Front
The Physics Front provides high quality resources for the teaching of physics and physical sciences courses. You may search or browse the Physics Front in order to find materials appropriate for your physics classes. Additionally, registering will allow you to share your experiences using materials. The Physics Front is a free service provided by the American Association of Physics Teachers in partnership with the NSF/NSDL.
See this page.
Physics Win or Physics Fail?
Use your knowledge of physics to put these videos to the test!
Inspired by Rhett Allain's physics explanations at Dot Physics, Dan Meyer's blog series "What Can You Do With This?", and Dan's TEDx plea for a math curriculum makeover, I have been collecting video clips that are prime for my physics students to analyze.
Videos are categorized by topic to help teachers locate videos for the concepts at hand. Several videos are listed under multiple topics. The videos are presented without any further questions other than "Physics win or physics fail?" (real or fake?)
Pretty Good Physics
If you are looking around for some good labs to use or to tweek, check this site out. Items have been put here for physics teachers, by physics teachers, and range from first-year high school physics to AP material. The emphasis is on labs, but explanatory material is also available. The University sources on the bottom will direct you to even more great material. The collection of materials is growing all of the time.
Vocabulary/Glossary
Electromagnetic Wave: A transverse wave consisting of oscillations of an electric field and a magnetic field at right angles to each other.
Electromagnetic Spectrum: The spectrum containing electromagnetic waves ranging in wavelengths and frequencies spanning the Radio, Microwave, Infrared, Visible, Ultraviolet, X-ray and Gamma Ray Regions.
Reflection: The phenomenon of light interacting with a surface and "bouncing" off of it such as with a mirror or an opaque object.
Mirror: A surface on which incident parallel light rays bounce off at an equal angles to a line drawn normally to the surface.
Angle of Incidence: The angle between an incident light ray and the normal line to the surface of a mirror.
Normal Line: The line drawn perpendicular to a mirror or transparent surface used as a reference to measure the angles of reflected and refracted light rays.
Angle of Reflection: The angle between a reflected ray and the normal line to the surface of the mirror.
Ray Diagram: A tracing of light rays used to locate real and virtual images for mirrors and lenses.
Real Image: An image created by focusing light from an object off of a mirror or through a lens in such a way that the light will be projected onto a screen.
Virtual Image: An image created by light from an object bouncing off of a mirror or passing through a lens in such a way that the light appears to be coming from a position it could not possibly come from such as behind the mirror or the enlarged image seen through a magnifying glass.
Focal Length: The distance between the focal point and the center of a mirror or lens.
Refraction: The bending of a light ray caused by its change in velocity at the boundary as it passes from one medium to another.
Index of Refraction: The index of refraction is defined as the ratio of the speed of light in free space to the speed in a medium n = c/v .
Snell's Law: Relates the angle of incidence to the angle of refraction for a light rays passing from one medium to another through the equation n1sinθ1=n2sinθ2
Magnification: The ratio of the size of the image produced by a mirror or lens to the size of the actual object.
Total Internal Reflection: The reflection of a light ray as it tries to pass from a material which has a higher index of refraction to one with a lower index of refraction. This reflection only occurs for rays incident at angles greater than the critical angle.
Critical Angle: The angle at which light stops undergoing refraction when trying to pass from a medium having a higher index of refraction into one with a lower index of refraction and follows a path parallel to the boundary instead. At angles greater than the critical angle the light reflects back into the original medium.
Dispersion: The separation of white light into its different constituent colors due to refraction and the dependence of the index of refraction on the wavelength of light.
Interference:
Diffraction: The bending of waves around the edges of objects or as they pass through narrow slits or apertures. Diffraction leads to the observed interference of light waves.
Photon: A small "bundle" or localized region of electromagnetic energy travelling at the speed of light and possessing frequency and transferable momentum but no mass.
Photoelectric Effect: When photons of Electromagnetic Radiation are incident upon a metal, the electrons at the surface of the metal absorb the energy. When light of high enough frequency is used electrons can be detected as being ejected from the surface. The action of the electrons being ejected depends on the frequency of the light and not its intensity as would be expected from classical wave physics demonstrating that in this way light behaves like an electromagnetic particle not like a classical wave.
University of Colorado PhET Simulations
Each of the following visually appealing and engaging simulations allow students to experience and experiment with various configurations of Light and Optics as a powerful supplement to real world experimentation. Students may interact with and vary the physical parameters of the simulations. Many of the simulations allow students to visualize and engage with phenomena that cannot be done in the high school lab setting. All of these simulations have accompanying lesson plans, student documents, and teacher resources developed by teachers for you to use in your classroom.
Radio Waves & Electromagnetic Fields: (9P.2.3.3.1 )Broadcast radio waves from PhET. Wiggle the transmitter electron manually or have it oscillate automatically. Display the field as a curve or vectors. The strip chart shows the electron positions at the transmitter and at the receiver.
Geometric Optics: (9P.2.3.3.3 )How does a lens form an image? See how light rays are refracted by a lens. Watch how the image changes when you adjust the focal length of the lens, move the object, move the lens, or move the screen.
Wave Interference: (9P.2.3.3.4)Make waves with a dripping faucet, audio speaker, or laser! Add a second source or a pair of slits to create an interference pattern.
Photoelectric Effect (9P.2.3.3.4)
Use this simulation from PHET and these teacher created worksheets to help students work through the photoelectric effect.
Bending Light (9P.2.3.3.2) (9P.2.3.3.4)
Explore bending of light between two mediums with different indices of refraction. See how changing from air to water to glass changes the bending angle. Play with prisms of different shapes and make rainbows.
The Electromagnetic Spectrum (9.2.3.2.7)
This unique NASA resource on the web, in print, and with companion videos introduces electromagnetic waves, their behaviors, and how scientists visualize these data. Each region of the spectrum is described and illustrated with engaging examples of NASA science. Come and explore the amazing world beyond the visible!
The following Videos are from the Annenburg Foundation's Mechanical Universe Collection Video on Demand
This series helps teachers demystify physics by showing students what it looks like. Field trips to hot-air balloon events, symphony concerts, bicycle shops, and other locales make complex concepts more accessible. Inventive computer graphics illustrate abstract concepts such as time, force, and capacitance, while historical reenactments of the studies of Newton, Leibniz, Maxwell, and others trace the evolution of theories. The Mechanical Universe helps meet different students' needs, from the basic requirements of liberal arts students to the rigorous demands of science and engineering majors. This series is also valuable for teacher professional development.
See this page.
40. Optics (9P.2.3.3.4)
Many properties of light are properties of waves, including reflection, refraction, and diffraction.
HippoCampus is a project of the Monterey Institute for Technology and Education (MITE). The goal of HippoCampus is to provide high-quality, multimedia content on general education subjects to high school and college students free of charge. This site could be used in conjuction with your course to help teach the standards at various levels or support student learning outside the classroom.
Electromagnetic Wave Basics (9P.2.3.3.1,9P.2.3.3.2)
Reflection, Refraction, and Total Internal Reflection (9P.2.3.3.3 ,9P.2.3.3.4)
Mirrors and Lenses (9P.2.3.3.3 ,9P.2.3.3.4)
Diffraction and Interference (9P.2.3.3.4)
Quantum Theory of Light (9P.2.3.3.4,9P.2.3.3.5)
Win/Fail Physics!
Use your knowledge of physics to put these videos to the test!
Inspired by Rhett Allain's physics explanations at Dot Physics, Dan Meyer's blog series "What Can You Do With This?", and Dan's TEDx plea for a math curriculum makeover, I have been collecting video clips that are prime for my physics students to analyze.
Videos are categorized by topic to help teachers locate videos for the concepts at hand. Several videos are listed under multiple topics. The videos are presented without any further questions other than "Physics win or physics fail?" (real or fake?)
Assessment
Assessment of Students
Physics classroom: Basic of Waves Review questions
Physics classroom: Interference, Polarization and Color Review questions
1. A ray of visible light passes from air into glass at an angle of incidence of 20 deg. What will be the angle of refraction?
a. 30 deg.
b. 25 deg.
c. 20 deg.
d. 15 deg.
e. 90 deg.
Answer D (9P.2.3.3.4)
2. Sunlight that passes through a prism is broken into a rainbow spectrum light because:
a. of total internal reflection.
b. of regular reflection
c. the index of refraction depends upon wave amplitude.
d. the index of refraction depends upon the wavelength.
Answer D (9P.2.3.3.4)
3. A laser light passing through a narrow slit produces the pattern as shown below What property of light makes this possible?
a. The light is primarily composed of particles
b. The light is primarily a wave
c. Laser light is red
d. Laser light is polarized
e. it is completely unknown why this pattern is formed
Answer B (9P.2.3.3.5)
4. What is the ratio of the frequency of blue light (l = 400 nm) compared to the frequency of infrared light (l = 1000 nm) in vacuum?
a. The two types of light have the same frequency.
b. 0.4 times
c. 1.6 times
d. 2.5 times
e. 1000 times
Answer D (9P.2.3.3.6)
5. What is the ratio of the speed of blue light (l = 400 nm) compared to the speed of infrared light (l = 1000 nm) in a vacuum?
a. The two types of light travel at the same speed.
b. 0.4 times
c. 1.6 times
d. 2.5 times
e. 1000 times
Answer A (9P.2.3.3.6)
6. Monochromatic light (l = 500 nm) is incident on a soap bubble (n = 1.4). What is the wavelength of the light (in nm) in the bubble film?
a. 255
b. 500
c. 700
d. 357
e. 422
Answer D (9P.2.3.3.4)
7. The bright and dark bands you see in a photograph of a double slit interference pattern represent
a. the respective positions of the crests and the troughs of the light wave.
b. an interference pattern that is not present unless it is produced by the camera lens.
c. the respective positions of constructive and destructive interference of light from the two sources.
d. the respective positions of destructive and constructive interference of light from the two sources.
e. the respective positions of bright and dark particles of light.
Answer C (9P.2.3.3.4)
8. All of the following are electromagnetic waves EXCEPT
a) radio waves.
b) microwaves.
c) light waves.
d) x rays.
e) None is outside the family; all are electromagnetic waves.
Answer E (9P.2.3.3.6)
9. To view your full-face image in a steamy mirror, compared to the height of your face, the minimum height of the patch to wipe away is
a) one-quarter.
b) one-half.
c) the same.
d) dependent on your distance from the mirror.
Answer B (9P.2.3.3.4)
10. Which of these changes when light refracts in passing from one medium to another?
a) Speed.
b) Wavelength.
c) Both of these.
d) Neither of these.
Answer C (9P.2.3.3.2)
11. the figure shows a possible path of light indicated by blue, red, or black through a glass block. Which path would be the fastest to the ending point where they meet?
a. blue path
b. red path
c. black path
d. they would each take the same amount of time.
e. It depends on the thickness of the glass block.
Answer B (9P.2.3.3.3)
12. Light of wavelength 600 nm in vacuum enters a block of glass where n = 1.5. Compute the wavelength in the glass.
a. 200 nm
b. 300 nm
c. 400 nm
d. 600 nm
e. 900 nm
Answer C (9P.2.2.2.2)
13. In an electromagnetic wave, how are the electric and magnetic field directions related to the velocity of light (c is the velocity of the light wave)? ^ means perpendicular
a. E || B || c.
b. E || B ^ c .
c. E ^ B ^ c.
d. E ^ B || c.
e. E = B = c.
Answer C (9P.2.2.2.1)
14. The solar constant is about 1400 W/m2 at the Earth's surface. If we assume an average wavelength of 700 nm, how many photons arrive per second per square meter on a solar panel?
a. 103
b. 106
c. 1012
d. 1014
e. 1020
Answer E (9P.2.3.3.5)
Modeling Physics Resources in Electricity and Magnetism at Arizona State University
Peer Instruction: A User's Manual, (Mazur, Eric, Harvard University, Prentice Hall, 1997) - conceptual questions for using Student Response Systems.
See this page.
Optics questions:
CT1: Refraction and principle of least time (9P.2.3.3.2) Answer D
CT2: Refraction and principle of least time (9P.2.3.3.2) Answer D
CT3: Polarization of light (9P.2.3.3.5) Answer A
CT5: Relfection in a mirror (9P.2.3.3.4) Answer D
CT6: Refraction of light through glass (9P.2.3.3.4) Answer B
CT7: Refraction of light from water (9P.2.3.3.4) Answer C
CT8: Refraction of light from water (9P.2.3.3.3) Answer C
CT10: Image produced by a half covered lens (9P.2.3.3.3) Answer E
CT11: Image produced by a lens in an overhead projector (9P.2.3.3.3) Answer A
CT14: Interference by two slides (9P.2.3.3.4) Answer A
CT18: Diffraction of Light by a slit and Huygens principle (9P.2.3.3.5) Answer C
CT20: Diffraction of light by a thin slit (9P.2.3.3.5) Answer B
CT25: Wavelength of light colors and resolution in a lens (9P.2.3.3.6) Answer D
1. What causes the colors formed by shining white light through a prism? Does the angle of refraction for the each color depend on the velocity change of the wave color, frequency change of the wave color, or change in wavelength of the color or a combination of the above? What does this say about the index of refraction for a material? (Answers or discussion points. The index of refraction for a medium varies as a function of the wavelength of light. The velocity of blue light is slower in glass than the velocity of red light so blue light refracts to a slightly greater extent. The double bending of light in the same direction caused by the shape of the prism allows for enough dispersion of the colors over a relatively short distance so as to be noticeable. It is interesting to note that the frequencies of the light do not change as they enter or leave the medium.)
2. What happens to a real image formed from a lens or a mirror if you cover up half of the lens or mirror? Do you see half of the object? If so explain why? If not explain what you would see and why.
(Answer or discussion points. A common misconception is that half of the object will be blocked at the location of the real image. Actually all that happens is that the intensity of the image is decreased. Rays of light obey the laws of optics for all parts of the mirror so the image will even if half a convex lens or concave mirror is used.
Assessment of Teachers
Modeling Instruction in High School Physics, Chemistry, Physical Science, and Biology
Materials and readings for teacher discussion and use for professional development
The Modeling Method of High School Physics Instruction has been under development at Arizona State University since 1990 under the leadership of David Hestenes, Professor of Physics. The program cultivates physics teachers as school experts on effective use of guided inquiry in science teaching, thereby providing schools and school districts with a valuable resource for broader reform. Program goals are fully aligned with National Science Education Standards. The Modeling Method corrects many weaknesses of the traditional lecture-demonstration method, including fragmentation of knowledge, student passivity, and persistence of naive beliefs about the physical world. Unlike the traditional approach, in which students wade through an endless stream of seemingly unrelated topics, the Modeling Method organizes the course around a small number of scientific models, thus making the course coherent. In 2000 the program was extended to physical science and in 2005 to chemistry, by demand of committed teachers.
See this page.
Peer Instruction: A User's Manual, (Mazur, Eric, Harvard University, Prentice Hall, 1997) - conceptual questions for using Student Response Systems.
See this page.
Optics questions:
CT1: Refraction and principle of least time (9P.2.3.3.2) Answer D
CT2: Refraction and principle of least time (9P.2.3.3.2) Answer D
CT3: Polarization of light (9P.2.3.3.5) Answer A
CT5: Relfection in a mirror (9P.2.3.3.4) Answer D
CT6: Refraction of light through glass (9P.2.3.3.4) Answer B
CT7: Refraction of light from water (9P.2.3.3.4) Answer C
CT8: Refraction of light from water (9P.2.3.3.3) Answer C
CT10: Image produced by a half covered lens (9P.2.3.3.3) Answer E
CT11: Image produced by a lens in an overhead projector (9P.2.3.3.3) Answer A
CT14: Interference by two slides (9P.2.3.3.4) Answer A
CT18: Diffraction of Light by a slit and Huygens principle (9P.2.3.3.5) Answer C
CT20: Diffraction of light by a thin slit (9P.2.3.3.5) Answer B
CT25: Wavelength of light colors and resolution in a lens (9P.2.3.3.6) Answer D
Differentiation
Strategies from The Inclusive Classroom: Teaching Mathematics and Science to English-Language Learners, (Jarrett, Denise, Northwest Regional Educational Laboratory, Nov. 1999)
Thematic Instruction: Theme-based units can help ELL students connect prior knowledge to language and real-world applications.
Cooperative Learning: Students use language related to task, while conversing and tutoring one another.
Inquiry and Problem Solving: Inquiry and problem solving can be used prior to proficiency in English. Inquiry approaches in science can help student's language acquisition as well as their content knowledge.
Vocabulary Development: Students learn the meaning of words best during investigations and activities, instead of as a vocabulary list.
Modify Speech: Teachers can help ELL students by using an active voice, limiting new terms, using visual support, and paraphrasing or repeating difficult concepts. Slowing down speech, speaking clearly, and using a simple language structure will help ELL students with understanding.
Make ELL Students Feel Welcome: Encourage ELL students to express ideas, thought, and experiences. Focus on what student is say, not how they say it.
Planks Constant Lab using LED's from the Perimeter Institute
Planck's constant (h = 6.63 x 10-34 Js) is a universal constant that lies at the heart of quantum physics. This resource centres around a laboratory activity in which students measure Planck's constant using a simple electronic circuit. The circuit is inexpensive and contains only a 6-volt battery, an LED, a resistor, a voltmeter, a few wires, and a potentiometer (variable resistor).
Book: Science Education for Gifted Students: A Gifted Child Today Reader (Johnsen, S. K. and Kendrick, J., 2005, Prufrock Press, Inc.)
A substantial resource for SpEd, ELL with specific suggestions for science classrooms. Teaching Today | How-To Articles | Supporting Special Education Students in Science
See this page.
Parents/Admin
Administrators
Ideas adapted from Best Practice: Today's Standards for Teaching and Learning in America's Schools (Daniels, H, Hyde, A, and Zemelman, S, Heinemann, Portsmouth, NH, 2005).
1) Students being challenged in thinking how magnetic and electric fields differ from each other, how light properties effect the way light moves under different conditions, and how light sometimes acts like a wave and sometimes acts like a particle.
2) Students testing their understanding of the electromagnetic properties of light with investigations or solving real life scenarios using the concepts and associated equations.
3) Students taking on responsibility for their own learning.
4) Student working in collaborative groups, analyzing, synthesizing, and defending conclusions.
5) Students sharing explanations for results of investigation and understanding of concepts.
6) Students continuously assessing and being assessed on their understanding of light and other electromagnetic frequencies.
7) Students concepts are being built on prior knowledge of motion, forces, magnetic fields and electric fields.