Test 2 News Keep your Tests in your notebook but
return your Scantron forms and the Manipulative. Some of the questions will appear on the comprehensive final. Discuss questions that you missed with your team mates. The Plan
Locate your name tag.
Remove the team role name and leave it on the desk in front of you. Leave the team name sign on the desk as well. Get ready to move Remember Attendance
Sheets EGR Hands-on XO Gathers Supplies
COM Recorder + Chalkboard CO Speaks for the Team + Attendance
Chapter 14 & 15 Light and Color Inside My Eye Supplement
Parts of the Human Eye (Supplement Handout)
Cornea bends light Iris controls the amount of light Pupil - opening Lens focuses light onto retina
Retina back of eye Fovea center of your vision Optic Nerve signal wire (causes blind spot) Blind Spot Demo (Page 265) O X
Rods - brightness receptors Cones - color receptors Three Types: Red, Green, Blue Cones are more numerous in the center of your vision. Rods are more numerous around the periphery of your vision.
Demo Moving markers near periphery Color Deficiency Color Vision Colorblindness - about 10% of population
Red-green is predominant Yellow-blue - a few What is color? Different wavelengths of light are
perceived as different colors. White light contains equal amounts of these colors. (ROY G. BIV) Fill in the Blanks
absorb all of the pure Black objects _______ colors.
reflect all of the pure White objects _______ colors. transmit all of the Transparent objects _______
pure colors. Color Filters Red filters transmit red light and absorb the other colors.
Red objects reflect red light and absorb the rest. In red light, what color do the red petals
and green leaves of rose appear? Color Filters Red filters transmit red light and absorb the other colors.
Red objects reflect red light and absorb the rest. In red light, what color do the red petals and
green leaves of rose appear? Answers: Petals appear red Leaves appear to be black
Color Filters The following color filters are yours to keep in the zip-lock bags: Red, Green, Blue Yellow, Magenta, Cyan
Flashlights All flashlights must work for this exercise. Mixing Colored Light Color Addition
Additive Primary Colors: Red Green Blue
One can produce any color by varying amplitude and mixture or red, green and blue light. Color Addition Examples: Tiny dots called pixels on Color TV's and
Computer Monitors are colored only red, green, or blue. Color Addition Lab Exercise (two pages) Color Addition Equations
Remember Attendance Sheets (Role Rotation) XO EGR
Gathers Supplies Hands-on CO COM
Speaks for the Team + Attendance Recorder + Chalkboard Lab Exercises
White Light and Color Addition Wheels Everyone will color Roy G. Biv onto the 7 segment wheel. XO Red + Blue = ?
CO Red + Green = ? ENG Blue + Green = ? COM Red + Blue + Green = ? Mixing Colored Pigments Color Subtraction
Subtractive Primary Colors: Yellow Magenta Cyan
One can produce any color by varying the amount of yellow, magenta and cyan pigments. Color Subtraction Examples:
Newspapers, magazines, books Zip-lock with colored seals Color Subtraction Lab Exercise (two pages) Color Subtraction Equations
Color Subtraction Using Crayons Lab Exercise Chromatography Lab Exercise
Primary Colors White Red Green Blue Yellow Cyan Magenta
Pure Green Color Addition Primary Green Green
Complementary Colors - any two colors that add together to produce white e.g. magenta + green = white
Engineering Astronomy Physics And our flag was still there... Spiral
After Images and Conal Fatigue The human eye will see
complimentary colors after staring at a color picture. Demos: Colored Shapes Texas Flag American Flag Rose Lincoln
Lab Supplement Color a Flag with Complementary Colors Move this page forward
What color would we use so that the afterimage is red, white and blue? Write this on the supplement: Complementary Colors Use cyan, black, and green get an after image that is red, white and blue.
Optical Illusions Animation Transparent and Opaque Transparent
you can identify objects through it Translucent
(14.2) you see diffuse light coming through it Opaque
you cannot see any light coming through it Opaque objects cast shadows. Can Light Pass Through Lab Exercise
Transparency Lab Exercise Pattern for Flashlight Reflector Shield Lab Exercise Why? We want a point source of light rather than a beam
when we investigate the shadows created by opaque objects. Tall in the Shadow Lab Exercise Chapter 18 Spectra
The Electromagnetic Spectrum A range of light waves extending in wavelength from radio waves to gamma rays
The Electromagnetic Spectrum On Chalkboard The Electromagnetic Spectrum Radio Waves Microwaves
Infrared Visible Light Ultraviolet X-rays Gamma Rays Which form of light has the
longest wavelength? highest frequency? highest energy? fastest speed? The Electromagnetic Spectrum Radio Waves Microwaves
Infrared Visible Light Ultraviolet X-rays Gamma Rays
mnemonic
Raging Martians Invade Roy G. Biv Using X-rays and
Gamma Rays Radio Waves Microwaves Infrared
Visible Light Ultraviolet X-Rays Gamma Rays
SPF The SPF of a sunscreen is a laboratory measure of the effectiveness of sunscreen; the higher the SPF, the more protection a sunscreen offers against UVB (the ultraviolet radiation that causes sunburn). The SPF indicates the time a person can be exposed to sunlight before getting sunburn with a sunscreen applied relative to the time they can be
exposed without sunscreen. For example, someone who would burn after 12 minutes in the sun would expect to burn after 2 hours (120 min) if protected by a sunscreen with SPF 10. The Visible Spectrum A range of light waves extending in wavelength
from about 400 to 700 nanometers. Things that create a Spectrum Prism Raindrops CDs Spectroscopes
Contains a Diffraction Grating Diffraction Grating for Ziplock Bag Creating a Spectroscope
Roll up and tape black paper to form a tube. Cover end of the tube with foil.
Use a blade to make a slit in the foil. Temporarily tape the diffraction grating over the other end of the tube. Observe several light sources. Incandescent Light, Florescent Light, Neon Sign
Object Names Blue Bowl Red Bowl
Yellow Post-it Orange Post-it http://sciencekit.com/ Object Names
Red Filter Green Filter Yellow Filter Cyan Filter
Gustav Kirchhoff Robert Bunsen The Taste Test versus The Flame Test
Continuous Spectra Hot, dense solids produce a continuous spectrum. (All Colors)
Emission Spectra Hot gas produces a bright line emission spectrum. (Bright Lines) Absorption Spectra
Filters behind continuous sources give absorption spectrum. (Missing Colors) Example Questions
What type of spectra do each of the following have?
Flashlight bulb Frosted Incandescent lamp Neon Sign
Florescent light Red bowl Hot Solids Hot Gasses Cool objects that reflect light Structure of the Atom
Proton Neutron Electron Energy Levels
Absorption When an electron is raised to a higher energy level, the atom is said to be excited.
Emission When the electron returns to a lower energy level, energy is released in the form of light. Element Fingerprinting
Different transitions from high levels to low levels result in different colors of light. Every element can be fingerprinted by it spectra.
Hydrogen Helium Oxygen Carbon
Every element can be fingerprinted by it spectra. Matching Questions Type of Spectrum Appearance 1. Emission Spectra a. All Colors
2. Continuous Spectra b. Dark Lines 3. Absorption Spectra c. Bright Lines Matching Questions 1. Emission Spectra a. Hot Solids
2. Continuous Spectra b. Cool Solids 3. Absorption Spectra c. Hot Gases
Incandescence The color of light emitted by hot glowing solids changes with its temperature.
Glowing object colors: Reddish
coolest glowing object Orange-ish Yellowish White Bluish hottest glowing object Example Questions
The star Sirius is blue and Arcturus is yellow. Which is hotter?
Answer: Sirius, Im not kidding. Consider a red filter and a blue filter. Which is hotter? Answer: They should be the same temperature because they are not glowing.
Fluorescence Some materials that are excited by ultraviolet light can emit visible light upon de-excitation. This is fluorescence.
Demo - Black light and chalk Fluorescent Lamps Primary excitation - electron collisions with
low pressure mercury vapor, and ultraviolet light is given off Secondary excitation - ultraviolet light is absorbed by phosphors and these emit visible light
Phosphorescence
Phosphorescence - a type of light emission that is the same as fluorescence except for a delay between excitation and deexcitation. Electrons get "stuck" in an excited state and de-excite gradually. Demos - glow-in-the-dark objects Lasers
Laser
Light amplification by stimulated emission of radiation Lasers produce coherent light. Coherent light means that all the light waves have the frequency, phase and direction. Demo - Laser and chalk dust Demo - Laser and prism or diffraction grating
Matching Questions 1. Incandescence a. mercury vapor light tubes 2. Fluorescence b. glow-in-the-dark paints and plastics 3. Phosphorescence
with filaments c. light bulbs Matching Questions 1. Fluorescent Lamp with temperature 2. Incandescent Bulb
of light 3. Laser c. converts visible light a. color changes b. only one color
ultraviolet light to Law of Reflection The angle of incidence equals the angle of reflection.
This is true for both flat mirrors and curved mirrors. Convex Mirror - security mirror
Concave Mirror - vanity mirror Demo: Chalk Dust and Concave Mirror Types of Reflection
Specular Reflection - images seen on smooth surfaces (e.g. plane mirrors) Diffuse Reflection - diffuse light coming from a rough surface (cannot see a reflection of yourself)
Movie Reflection Demonstrations
Candle in Water Video (Movie) Terminator II Movie Supplemental Handouts
Funny Face Reverse Images Make a Kaleidoscope Please bring your book to class
tomorrow. EGR Hands-on XO Gathers Supplies
COM Recorder + Chalkboard CO Speaks for the Team + Attendance
Notebooks Due on Wednesday before the Exam. http://observe.phy.sfasu.edu/courses/ phy410/homework/NOTEBOOK.doc Principle of Least Time
Fermat's principle - light travels in straight lines and will take the path of least time A B Wrong Path
True Path MIRROR Refraction
Refraction is the bending of light when it passes from one transparent medium to another. This bending is caused by differences in the speed of light in the media.
WATER WAVE MOVIE Refraction Light Beam
Normal Line Fast AIR WATER Slow Refraction Examples
Light slows down when it goes from air into water and bends toward the normal.
An Analogy: A car slows down when it goes from pavement onto gravel and turns toward the normal. MOVIE Index of Refraction n=c/v Refraction
Observer AIR WATER False Fish True Fish
Lab Exercises Refraction Cup of Water and Pencil
Broken Pencil Movie Finding Object Under Water
Refraction Activities Procedure 1 - Shallow Appearance Procedure 2 - Spearing a Fish Procedure 3 - Broken Images
Dispersion... is the separation of white light into pure colors (ROY G. BIV). Dispersion
Examples: Prisms Diffraction Gratings Rainbows
Raindrops refract, reflect and disperse sunlight. Rainbows will always appear opposite of
the Sun in the sky. You cannot run from or run to a rainbow!
How can you make a rainbow? Remember Attendance Sheets (Role Rotation) XO
EGR Gathers Supplies Hands-on CO
COM Speaks for the Team + Attendance Recorder + Chalkboard
Lenses Converging Lens
Diverging Lens A lens that is thicker in the middle and refracts parallel light rays passing through to a focus. A lens that is thinner in the middle than at the
edges, causing parallel light rays to diverge. Team Exercise: Lens sorting Myopia (Near-Sightedness) People with near-sightedness cannot see clearly at distance.
What kind of corrective lens will they need? Hyperopia (Farsightedness) People with far-sightedness cannot see clearly up close. What kind of corrective lens will
they need? Where is the Image? Lab Exercise Making a Telescope Lab Exercise
Total Internal Reflection... is the total reflection of light traveling in a medium when it strikes a surface of a less dense medium
Demo - Laser and light pipe Example: Optical Fiber Ring Laser Underwater Movie
Woman Edge Pool Movie Critical Angle AIR
WATER Total Internal Reflection Light Source
Atmospheric Refraction Our atmosphere can bend light and create distorted images called mirages.
http://astro.sfasu.edu/movies/Highway Mirage 1.mpg What causes stars to twinkle?
Atmospheric Turbulence Mirage Cool air Warm air Because of atmospheric refraction,
we have lingering, elliptical sunsets. Sun Sun Earth Why is the sky blue?
Nitrogen and Oxygen in our atmosphere scatter high frequencies of light. Why are sunsets red?
Red light is scattered the least by our atmosphere. The greatest path of sunlight through the atmosphere is at sunset or sunrise.
Why are clouds white? The color of light scattered by clusters of water molecules vary with the size of the clusters.
The size of clusters of water molecules (droplets) vary in clouds. Why is the ocean greenish blue?
Red light is absorbed by the molecules in the water. Review for Test 3 Chapter 14
Color Chapter 15 Refraction
Chapter 18 Spectra Chapter 14 Section 14.3 through 14.8
Selective Reflection Selective Transmission Color Addition Color Subtraction Complementary Colors Conal Fatigue Why is the sky blue?
Why Sunsets are Red Chapter 15 Section 15.2 through 15.6
Refraction - Bending Speed in different media Apparent Water Depth Illusions and Mirages Atmospheric Refraction Dispersion Rainbows
Lenses and Telescopes Your Eye Image Formation Exercises
Bob the Builder and Filter Glasses Goggles - Supplement Kaleidoscope Animal Shadow
Prism Power Chromatography Diffraction a modification which light undergoes in
passing by the edges of bodies or through narrow slits and in which the rays appear to be deflected and to produce fringes of parallel light and dark or colored bands Water Wave Interference Movie
Multiple Slit Interference Movie Doppler Effect
the change in wavelength due to motion of the source or observer "Wheeeeeeeeeeee.Oooooooooooooo
Examples: Water, Sound, and Light
Wavelength Source at Rest What happens when the source in in motion? Movie #1 Java
Long Wavelength Low Frequency Low Pitch Ooooooo!!! Short Wavelength High Frequency
High Pitch Weeeeeeeee!!! Source in Motion As a team, describe what happens to the wavelength, frequency,
and pitch both in front of and behind a moving sound source. Doppler Effect Examples:
moving cars and trains
Sound Movie #2 moving buzzer in a nerf ball (in class) Chapter 14 & 15 Light and Color
Be prepared to turn in your notebook at the beginning of Test 3. It will be returned at the end of Test 3. Please keep your notebook after that for your future class. Test 3 Everyone starts Test 3 at 1pm. Manipulative Transparent, Translucent, Opaque
Spectra, Color, and Lenses Pendulum (Optional) Remember Attendance Sheets EGR Hands-on
XO Gathers Supplies COM Recorder + Chalkboard
CO Speaks for the Team + Attendance Remember Attendance Sheets Your view
XO EGR Gathers Supplies Hands-on
CO COM Speaks for the Team + Attendance Recorder +
Chalkboard Chapter 14 & 15 Light and Color Remember Attendance Sheets (Role Rotation)
CO Speaks for the Team + Attendance COM Recorder + Chalkboard
XO Gathers Supplies EGR Hands-on Remember Attendance
Sheets (Role Rotation) COM CO Recorder +
Chalkboard Speaks for the Team + Attendance EGR XO
Hands-on Gathers Supplies Remember Attendance Sheets (Role Rotation)
CO Speaks for the Team + Attendance COM Recorder + Chalkboard
XO Gathers Supplies EGR Hands-on Remember Attendance
Sheets (Role Rotation) COM CO Recorder +
Chalkboard Speaks for the Team + Attendance EGR XO
Hands-on Gathers Supplies
