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  1. page Light edited ... Structure of the eye and how we see color: {http://www.nei.nih.gov/health/eyediagram/images/d…
    ...
    Structure of the eye and how we see color:
    {http://www.nei.nih.gov/health/eyediagram/images/diagram.gif}
    ...
    and physiological resposeresponse to light
    ...
    we see. Color is produced by what an object does not absorb. Whatever color it does not absorb, we see the color of that object as the color of light that was not absorbed. For instance, if a shirt reflects red light, then we see the shirt as red.
    Primary Colors of LightLight, Pigment, and Filters:
    light has

    The primary colors of light, the ones with the frequencies that are received by our cones, are red, green, and blue. These colors, when added together, create white light, while the absence of light creates the "color" black. These colors overlap each other, allowing for different colors, or the Additive Secondary Colors, which are cyan, yellow, and magenta, to exist. They are the complimentary colors of light, but they are the primary colors of pigments and filters. The primary colors of pigments and filters together form black, and the absence of these colors creates white.The filters let through only what color it is, so if a filter is cyan it lets in green and blue light out of the broad spectrum of light.
    The primary colors of light:
    {http://www.fas.harvard.edu/%7Escidemos/LightOptics/ColorMixing/ColorMixing06.jpg}
    The primary colors of pigments and filters:
    {http://www.novaprinting.ca/images/CMYK.jpg}

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    9:55 pm
  2. page Light edited ... Light moves in waves and travels at the constant speed of approximately 3x10^8 m/s. Nothing ca…
    ...
    Light moves in waves and travels at the constant speed of approximately 3x10^8 m/s. Nothing can ever reach this speed.
    The Electromagnetic Spectrum
    {http://zebu.uoregon.edu/~imamura/122/images/electromagnetic-spectrum.jpg}{http://zebu.uoregon.edu/%7Eimamura/122/images/electromagnetic-spectrum.jpg}
    The Electromagnetic Spectrum shows the frequencies and wavelengths for various types of radiation. Radiation is energy that transmitted in the form of waves or particles. The range of this electromagnetic radiation is known as light. An electromagnetic wave is composed of two parts: the amplitude which is the "brightness" of the light, and the wavelength which is related to the color. The wavelength of the wave is also the angle of which the wave is vibrating, known as polarization.
    Radio Waves - waves with the lowest frequencies and the longest wavelenghts of the waves in the Electromagnetic Spectrum
    ...
    results of neuclear interactions
    highest freqency waves on the spectrum
    Structure of the eye and how we see color:
    {http://www.nei.nih.gov/health/eyediagram/images/diagram.gif}
    The eye is a visual organ that detects light and sends impulses through the optic nerve to the brain in order to let the image be deciphered. Color, whose definition is "the psychological and physiological respose to light waves a a specific frequency or set of frequencies interacting with the eye", is picked up in the eye by the retina. There are two types of sensory cells in the retina: the rods and the cones. The rods in the eye are associated with light intensity, so they are optimal for vision in the dark. But cones react to different frequencies, more specific those of red, green, and blue light. The green cones are the most sensitive, covering the largest range of frequencies, while the blue and red cones are receptive to less frequencies. The frequencies of light that the cones receive also overlap each other, allowing for a greater variety of colors that we see.
    Primary Colors of Light and Filters:
    light has

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    9:33 pm
  3. page Cool Stuff! edited ... http://epicwinftw.com/2010/03/18/epic-win-photos-exploding-sticks/ And this, my friends, is w…
    ...
    http://epicwinftw.com/2010/03/18/epic-win-photos-exploding-sticks/
    And this, my friends, is what happens when you connect those two powerful currents of electricity. So never, ever do that. This causes a power outage, like squirrels do during rainstorms. When you connect the power line with another source, an arcing circuit will occur where the electricity escapes the current where it is supplying power to homes, etc. As for the squirrels, when they run on the power lines during rainstorms (water helps conduct the electricity) and jump to the power line poles or something similar, they connect and complete a circuit, which breaks the normal one running through the power line. Oh, and the squirrel dies, poor thing.
    Tesla coils Ghostbusters theme:
    http://www.viddler.com/explore/epicwinftw/videos/2/38.467/
    It's comforting to know that whatever song you play with any instrument, it will never be this awesome. Well it might be, but not on a scientific level.
    A physics-y show that everyone has to watch:
    http://www.youtube.com/show?p=Zk2dX5DnW_c
    Because watching Star Trek will make you that much more awesome.

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    8:55 pm
  4. page Orbits edited ... In our solar system, the Earth orbits the Sun, as do the other eight planets. They all travel …
    ...
    In our solar system, the Earth orbits the Sun, as do the other eight planets. They all travel on or near the orbital plane, an imaginary disk-shaped surface in space. All of the orbits are circular or elliptical in their shape. In addition to the planets' orbits, many planets have moons which are in orbit around them.
    Path and Shape of Orbits
    ...
    the planets. If you ever need a good simulation for visual learning, then go to this site: http://vimeo.com/2015277 it has a very nice demonstration of Kepler's laws.
    Kepler's 3 Laws of Planetary Motion:
    1. Planets orbit around the sun in elliptical patterns, not circular, around the sun.
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    8:36 pm
  5. page Electricity & Magnetism edited ... A battery is essentially a can full of chemicals that produce electrons. Chemical reactions th…
    ...
    A battery is essentially a can full of chemicals that produce electrons. Chemical reactions that produce electrons are called electrochemical reactions. If you look at any battery, you'll notice that it has two terminals. One terminal is marked (+), or positive, while the other is marked (-), or negative. In an AA, C or D cell (normal flashlight batteries), the ends of the battery are the terminals. In a large car battery, there are two heavy lead posts that act as the terminals. Electrons collect on the negative terminal of the battery. If you connect a wire between the negative and positive terminals, the electrons will flow from the negative to the positive terminal as fast as they can (and wear out the battery very quickly -- this also tends to be dangerous, especially with large batteries, so it is not something you want to be doing). Normally, you connect some type of load to the battery using the wire. The load might be something like a light bulb, a motor or an electronic circuit like a radio.
    Inside the battery itself, a chemical reaction produces the electrons. The speed of electron production by this chemical reaction (the battery's internal resistance) controls how many electrons can flow between the terminals. Electrons flow from the battery into a wire, and must travel from the negative to the positive terminal for the chemical reaction to take place. That is why a battery can sit on a shelf for a year and still have plenty of power -- unless electrons are flowing from the negative to the positive terminal, the chemical reaction does not take place. Once you connect a wire, the reaction starts. The ability to harness this sort of reaction started with the voltaic pile.
    Conductors and Insulators:
    Conductors and Insulators are materials that either conduct or do not conduct electricity. Conductors are the materials that conduct electricity. This is due to their valence electrons in the atoms of the material that interchange and allow electrical current to travel easily.
    A list of conductors:
    -metals (such as copper, aluminum, gold, silver, steel, iron, and brass)
    -water
    -concrete
    -mercury
    A list of insulators:
    -glass
    -rubber
    -oil
    -wood
    -air
    plastic

    Static electricity
    Static electricity is an electric charge built up on persons or objects through friction. It is most familiar as an occasional annoyance in seasons of low humidity, but can be destructive and harmful in some situations. When working in direct contact with integrated cicuit electronics, or in the presence of flammable gas, care must be taken to avoid accumulating and discharging static electricity.
    ...
    Everything we see is made up of tiny little parts called atoms. The atoms are made of even smaller parts. These are called protons, electrons and neutrons. They are very different from each other in many ways. One way they are different is their "charge." Protons have a positive (+) charge. Electrons have a negative (-) charge. Neutrons have no charge.
    Usually, atoms have the same number of electrons and protons. Then the atom has no charge, it is "neutral." But if you rub things together, electrons can move from one atom to another. Some atoms get extra electrons. They have a negative charge. Other atoms lose electrons. They have a positive charge. When charges are separated like this, it is called static electricity.
    ...
    each other.
    {kid-with-static-hair.jpg}
    ...
    move from your
    your
    hair to
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    8:29 pm
  6. page General stuff NEW edited General Physics Stuff PHYSICS IS..... ... 3. Consider the item you are measuring A final t…

    General Physics Stuff
    PHYSICS IS.....
    ...
    3. Consider the item you are measuring
    A final thought on uncertainty...
    ...
    in science?
    In

    In
    the sense
    ...
    analyzing results.
    2.

    2.
    SI Units
    ...
    International d'Unités)
    · A system of all units and weights
    ...
    20, 1875
    · Adopted by the 11th conference General Conference on Weight and Measures
    · Updated by Federal Bureau of Weights and Measures every few years with an international conference
    ...
    (http://en.wikipedia.org/wiki/SI_prefix)
    3. Problem Solving Format for Physics Problems
    Don't let your problem solving format look like this!!!!:
    {file:///C:/DOCUME%7E1/aschwarz/LOCALS%7E1/Temp/moz-screenshot-5.png} {http://www.onedividedbyinfinity.com/blogimgs/physics-toon.jpg}

    1. Focus the Problem
    2. Describe the Physics
    ...
    Examples: The Model of the Atom, The Standard Model
    Laws: A statement or relationship that is mostly but not necessarily always true.
    ...
    = -kx
    6. Proportionality
    Proportionality is the mathematical relation between two quantities. (if the ratio is constant)
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    8:08 pm
  7. page Cool Stuff! edited ​Cool Stuff! So basically this is where all the awesome things go that apply to physics/scien…

    ​Cool Stuff!
    So basically this is where all the awesome things go that apply to physics/science in general.
    Combusting stick on a power line:
    http://epicwinftw.com/2010/03/18/epic-win-photos-exploding-sticks/
    And this, my friends, is what happens when you connect those two powerful currents of electricity. So never, ever do that. This causes a power outage, like squirrels do during rainstorms. When you connect the power line with another source, an arcing circuit will occur where the electricity escapes the current where it is supplying power to homes, etc. As for the squirrels, when they run on the power lines during rainstorms (water helps conduct the electricity) and jump to the power line poles or something similar, they connect and complete a circuit, which breaks the normal one running through the power line. Oh, and the squirrel dies, poor thing.

    (view changes)
    8:03 pm

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