What is meant by the expression " Dispersion Of White Light"?
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Light of different wavelengths will have different refractive indices when entering a new medium (like glass) from air.  This means that they will bend to different degrees.  Hence, white light will be dispersed by passing through glass or water.  It's how a prism works, but it's also why serious astronomers use reflective telescopes rather than refractive telescopes.\n\nA normal mirror like the one in your bathroom will be aluminum on the back side of glass.  But the ones in big observatories are aluminized on the front side of the glass so that the light doesn't have to pass through a different media, which would cause not only dispersion, but loss of light.\n\nAt the observatory on Mount Palomar in California, I had an opportunity to see the chamber where the mirror is realuminized.  The mirror itself is made from pyrex glass, not due to the transparency of glass, but due to the resistance of the glass to changing size (and hence changing curvature) when its temperature changes.  When it's time to lay a new coat of aluminum (that's alumium for you Brittish-type English speakers) on the glass, the put the mirror in an air tight chamber that fits atop the mirror.  All air is sucked out of the chamber, creating a vacuum.  There are serveral tungsten filaments (the same material that makes the filament in a lightbulb) on the roof of the chamber, and on on these filaments a few aluminum clips are hung.  Then a charge is given to the hooks, and then a great current heats the filaments.  In the vacuum, the aluminum will vaporize.  The aluminum vapor will cling by static charge and condense on the glass, making a very, very fine coat of aluminum.\n\nTotal digression, I'm sure.  Cheers.
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It is due to the coherence of the laser light. Laser light is both monochromatic and coherent. Monochromatic means it is all the same color, or all the photons have the same wavelength. Coherence means that all the waves are in step with each other. Coherence causes interference patterns that you would not see in incoherent light. The specks are basically an interference pattern. So, yes, you could kind of think of that as if the photons were clumping up. Kind of.
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The "white" is caused by the crystalization of water molecules when they are frozen.  Light refracts off these crystals in a full spectrum (so you get white.)  When the molecules free again after getting warm, the light no longer refracts off in the full spectrum removing the white color.\n\nBTW white light is made of millions of colors...
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Light is a particle. Wave is its function.
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The proof is red-shift.\n\nAs things recede from each other at a high fraction of c (speed of light), the waves stretch out; visible light takes on a higher red content.  The SPEED of light remains the same, but the frequency changes.\n\nConversely, when things approach each other, they blue-shift; the light becomes more blue.
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well nwhen white light goes through a prisdim, it breaks and turns into the colors of the rainbow. so when white light goes through the atmosphere, which acts like a prism, it breaks and we mostly see the blue
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Iridescence is an optical phenomenon characterized as the property of surfaces in which hue changes according to the angle from which the surface is viewed, such as soap bubbles and butterfly wings.\n\nIridescence is caused by multiple reflections from multi-layered, semi-transparent surfaces where the subsequent phase shift and interference of the reflections modulates the incident light (by amplifying or attenuating different frequencies). This process is the functional analog of selective wavelength attenuation as seen with the Fabry-Perot interferometer.\n\nThe word is derived in part from the Greek word iris (pl. irides), meaning "rainbow", which in turn derives from the goddess Iris of Greek mythology, who is the personification of the rainbow and acted as a messenger of the gods.\n\nDictionary definition:\n\nThe visual property of something having a milky brightness, exhibition of rainbowlike colors on a surface. It usually results from interference when light composed of different wavelengths is reflected from the superficial layers of organic or inorganic substances, e.g., minerals, mother-of-pearl, and the feathers of birds. Iridescence greatly enhances the value of certain gems.
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Originally a spectrum was what is now called a spectre, i.e., a phantom or apparition.\n\nWhen white light is passed through a prism, colours 'appear' as if from nowhere, so this is where the link comes from
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Ordinary white light, like that from the sun, is made up of many different colors all of which have a different wavelength.  Normally, when we see light from the sun, it appears colorless.  However, Isaac Newton discovered in 1666 that when he passed regular sunlight through a prism (basically, a triangular piece of glass), the prism would split the light up into a band of colors. \n\nThe band of colors is called the spectrum which appears in the order of red, orange, yellow, green, blue, indigo, and violet. \n\nWhen it rains, the air is filled with raindrops.  These raindrops act like a prism.  If sunlight passes through the raindrops at the proper angle it is split into its spectrum, which is made up of the colors of the rainbow. \n\nYou can make your own rainbow at home by filling a plastic box with water and placing it near a sunny window.  If the wall next to the window isn’t white, place a piece of white paper next to the window.  Next, place a mirror inside the box of water facing the window.  The mirror needs to be tilted towards the sunlight.  The wedge of water in the front of the mirror acts as the prism and the mirror reflects and image of a rainbow on your wall
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I believe transmissivity refers to how much light can pass through the diode, as in a transparent solar panel, etc.
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i would say it's a colloid\n\ncolloid="In general, a colloid or colloidal dispersion is a substance with components of one or two phases, a type of mixture intermediate between homogeneous solution and heterogeneous mixture with properties also intermediate between a solution and a mixture."----basically meaning solids suspended in a liquid
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Ignore the above answers they are all horribly wrong. This is a chemistry question.\n\nColors in chemistry are due to two main phenomena. \n\n1. Light Absorption\n2. Charge Transfer\n\n\nFor the first case an electron can be promoted to a higher energy state by absorbing light energy. White light consists of wavelengths (about) 400-800 nanometers. Wavelength is inversly related to frequency which is related to the energy of light. The photonic energy of the light from certain wavelengths is absorbed to promote an electron. The rest of the light is transmitted. This transmitted light is what we see. But also keep in mind that the eye works strangely and we see mixed colors a little different.. I dont know why but just keep it in mind.\n\nThe second phenomena is charge transfer. This occurs when  an electron is transferred from one atom to to another. An example is KMnO4 (which has no d electrons) but is purple! This is because a electron is transferred from the oxygen to the manganese. \n\nAnd there are some other mechanisms for which colors are produced. One of the latest is now understood by a physics professor at ucla. Hes been studying how sound can interact with a bubble to produce light.
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It's just a light thing.  I've studied this for art more than for science...um, red light is the shortest wavelenth, so it's the first to be filtered out by distance.  If they're far enough away, only the blues and purple wavelengths make it to your eyes.
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It is how opaque a material is.\n\nIt is measured by how much light can be seen through the material.
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Well.. you say white light it's not refracted by glass... Then if that's true, there shouldn't be a rainbow EVER, no?\nThat's the point, white light it's composed by several colors, that's why it's white. When it goes through a glass, it WILL be refracted, causing it to separate into different spectres of light. Of course, only a minimal part of it will be refracted, for those glasses are constructed in such a way to prevent it from doing so.
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No. Wave dispersion separates frequencies. The Doppler effect is caused by motion towards or away from a source, altering the perceived frequency.
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All of the light "floating" in the air is composed of photons which are eventually absorbed by the atoms in the room and converted into heat.  This heat eventually dissapates through the walls and radiates outside the room.  Of course, there is an imperceptable delay between when the last photon leaves the light and is absorbed by the walls, but this happens at the speed of light and can't be seen by you or me.