Dec 17, 2015
Radio Waves- The longest of the wavelengths- Lowest frequency- Includes microwaves- Lowest photon energy – photons are tiny particle bundles of radiation- Microwaves of a microwave oven
Infrared Waves- Slightly longer than visible light-The warmth you feel from the sun causing skin molecules to vibrate more increasing their kinetic energy as well as skin temperature.- Infrared binoculars, to see heat- IR seekers, spyware
Visible Light Waves
- Visible radiation- The only visible part of the electromagnetic spectrum (ES)- Causes chemical reactions to green plants, photosynthesis, to make their own food- Stimulates chemical reactions in our eyes so we can see
Ultraviolet Radiation
- Higher frequency than visible light, more energetic and greater penetrating power than photons of visible light- Kills bacteria, sterilize surgical instruments, too much kills healthy cells- Prolonged exposure, dry skin, sagging and skin cancer
X Ray Waves- Shorter wavelength, higher frequency than UV radiation waves- Medical X Rays travel through skin and muscles, but bone and teeth are too dense- Airport scanners for luggage
Gamma Rays- Highest frequency- Highest penetration of EM waves- Opposite of radio waves- Emitted from nuclei of radioactive atoms- Can be used to kill cancer cells
List of WavesRadio R__________Infrared I_________Visible V__________Ultra Violet U__________X rays X___________Gamma G___________
List of WavesRadio RaccoonsInfrared InvadeVisible VillagesUltra Violet UsingX rays X rayGamma Goggles
Visible LightTransparent Light
Light can pass through clear objects like glass or clear plastics.Nearly all light is reflected or absorbed.
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Visible LightTranslucent Light
Objects that allow some light to pass through like waxed paper or frosted glass.Some light passes through but you cannot clearly see the object.
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Visible LightOpaque Material
Materials that reflect all light. Objects you cannot see through such as a bowling ball or basketball or cardboard box.
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Visible LightColor
When we see “White” all light is reflected in the visible spectrum.Blue jeans are “Blue” since all light on the jeans is absorbed except the “Blue” which reflects back to your eyes creating a chemical reaction in your eyes.Grass is green for the same reason.
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Visible Light Cones and Rods
How do we see color?Light waves enter the eyes and focuses on the retinas made of 2 types of nerve cell photo receptors. A chemical reaction takes place.One photo receptor, “Cones” is used for color and detailed shapes. 3 cones, red, blue and green.The other photo receptor, “Rods” sensitive to dim light, used for night vision.
Visible LightColor Blindness
An inherited condition when cones do not function properly. The inability to distinguish between some colors.
8% of men are colorblind0.5 % of women are colorblind.
Visible LightColor Blindness
Colorblind test. Open hyperlink.http://www.maniacworld.com/color_blind_test.htm
Remember this is only an example of a test. Do not panic if you do not “score” well.
Visible LightPigments
Used by artists to make colors of paints and inks for printing purposes.By mixing 3 pigment colors you can create most any color desired. The combination of all 3 pigments, yellow, cyan and magenta creates black.Yellow + Cyan + Magenta = Black
Light Wave Behaviors
RefractionThe bending of light waves caused by change in their speed as they move from one medium to another.
Light Wave Behaviors
DiffractionThe bending of light waves round parallel slits such as a “CD”. As white light shines through a diffraction grating the colors separate.
Light Wave BehaviorsInterference
The passing of light of a uniform wave length through a narrow slit, than adding another wave causes interference such as a holographic image.