<Part II to:  What is Light?>\nOk, I can turn my light switch on and off … the light that was in the room is “oscillating magnetic fields”… what is stopping the light from fluctuating through a wall into the next room?  And if light is constantly on the move in waves, technically, where does light end?
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Not alot actually. Photons bounce around like crazy. When white light strikes a surface some of it is absorbed by the molecules in it. The rest bounces off. When that light hits your eye you see the light whithout the wavelength the surface absorbed giving you the perception of colour. If all light was stopped by matter it would be pitchblack all around you. \n\nNo surface reflects 100% of the infalling light however. Some is always absorbed by atoms and molecules (that become excited ot more energetic) no mather how reflective the surface or transparent the substance. Water may appear completely transparent but only a few hundred meters beneath the surface of the ocean it is quite dark because the water has absorbed the sunlight.\n\nLight ends when a photon is unable to move. A photon is composed of an electric wave and a magnetic wave. Pure energy that is. The higher the frequency of the photon the less likely it is to be stopped by an atom (atoms are composed mainly of empty space). So gamma rays (the photons with the highest energy) are able to pass through matter. But most photons will be stopped by an atom eventually and when that happens the energy of the atom is taken up by the electron in it. The electron moves into a higher orbit: the atom has become excited. Usually, when the electron moves back into its ordinary orbit, the energy is rereleased as heat (low energy infrared photons). Sometimes the energy is rereleased as a photon of a different colour (frequency). The substance glows.
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lights off...but candles lit.  but be careful...we don't want a fire...might ruin the moment.  Candles lit...or just a dim light because it's more flattering than a bright light.  (i need all the help i can get after having an 8 pound baby!)  you wanna be able to see something...that's why I need SOME light.\n\nhope that helps.
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there is two rooms one with 3 light switches the other with 3 lightbulbs one for each switch.  you have to figure out wich switch goes to wich bulb.  you cannot see into the other room from the one you are in, and you are only allowed one trip to the room with the lightbulbs
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Forever and ever.\nIt may get dimmer, but that is from the spreading of the light.  The photons will travel until they collide with something.
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Hmmmmmm, not entirely sure what you are on about here, so lets talk about the double slit experiment.\n\nFirst of all, I thought what was happening in the double slit experiment was DIFFRACTION and not refraction. Refraction occurs when light travels through mediums with differing densities.\nOk, so you have a monochromatic light source, lets say a laser. Now this must be done with monochomatic light, because we want the light to interfere with ITSELF, to produce the diffraction pattern. Now the slits in the experiment must have a width less than the wavelength of the light. If the slit was bigger, then the light would simply pass straight through the slit, and just produce a classical DOT on the screen. \n\nSo the incoming laser light, hits the slits. No here's the interesting bit. When light tries to travel through a hole that is too small, normally we would expect, that it just cant go through!!! But light is a tricky bugger, and DOES go through. The edges of the slit, cause the light beam to BEND!!! Now this might seem like refraction, however the bending occurs to the extent that the linear propogating wave, now acts as a point source at the slit!!!!!! Huh???? Well instead of the light looking like it came from a laser at the slit, the light now looks like it is coming from a monochromatic light bulb at the slit. So BOTH slits act as if there are TWO point sources of monochromatic light. Both these point sources are EXACTLY in phase with one another. You can imagine this as simulataneously dropping TWO pebbles into water, a foot apart. What you see in the water is two radiating ripple patterns. When the ripples hit each other, you get constructive (the waves add together), and also destructive (the waves subtract from one another, hence cancel) interference patterns. \nYou could sit down and play with the trigonometry of the situation, but lets keep the maths out of it. Draw on a piece of paper, two dots seperated by a distance. Now using a compas draw bigger and bigger circles around your dots. Keep the same radius increments for both dots. As you draw more circles you will see that you start to draw over the top of the circles from the neighbouring hole. Keep going draw lots of circles!!!!!! OK, now look at where your circles overlap and touch one another. You could draw a line connecting these points. In the middle of the slits/dots, you will notice that your circles overlap forming a straight line moving away from the slits/dots. This is the PRIMARY interference fringe!!!! To the left and right of the Primary are the secondaries, which are less intense.\n\nAnyway, the point is, that the light source needs to be monochromatic, and that the slits need to be smaller than the wavelength of your light.\n\nHmmmm, the above experiment was thought to be excellent evidence that light is a wave!!!! HOWEVER. This same experiment has been done firing individual photons at the same slits. What you see initially is just a dot which appears at some location on the screen. The next dot may be somewhere else. But over time, the dots still build up the SAME interference pattern. Without going into it in too much detail, this is an ODD result!!!!\n\nIn the end, this experiment suggests that interactions on these scales are determined by PROBABILTIES of how wave functions add, and subtract from one another. There are several possible outcomes that light can take upon emerging from the slits. The primary fringe has the highest probability, and thus, the majority of photons will hit this location. Thus this fringe is the BRIGHTEST. The spots that appear perpendicular (at right angles) to the slits, have the lowest probability, and thus are the weakest!!!!! If you wish to do this experiment yourself at home, simply get out your laser pointer, and shine it onto a CD or DVD, and reflect the beam onto a screen, or wall etc. The little pits on the CD act like the double slits in this experiment. Thus your ONE laser pointer, can turn into MA
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Light has a dual nature. Or, better yet, it has a nature that depends on the observer.  The fantastic results of light experiments are fueling debates even now, half a century after quantum physics was born. I suggest you watch a movie called "What the bleep! do we know?  Or read books by Fred Alan Wolfe.
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The speed of light is invariant---no matter how fast or slow its source is moving, the speed of light remains unchanged (...please don't ask 'why?' because nobody has the vaguest idea) If you're in spaceship going at 99% the speed of light and shine a light outward in any direction, that light will move away from you at the speed of light, no faster, no slower.\n\nWith regards to the answer given that mentions the Doppler effect. The FREQUENCY (wavelength) of light is affected by the speed of the light source (Doppler effect), but frequency has nothing to do with the actual velocity of the light itself.
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Yes, yes, yes, yes..!!! Scientists have stopped light.\n\nThe details of when, where and how are here ---\nhttp://science.nasa.gov/headlines/y2002/27Mar_stoplight.htm\n\nhttp://physicsweb.org/articles/world/14/9/8
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Don't think of Lightening as a form, think of it as a force.  The force manifests itself in that bright column as that force moves through the air.  Take a look at this video, not only is lightening not completely understood by science but our ideas about what triggers it are changing.
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basic principles of wave propigation. a body in motion tends to stay in motion. if what you're saying is the vacuum is deviod of all matter, including subatomic particles, the wave would continue forever, with one exception. if the beam reflecting around the room collided with itself (say it caught itself in a corner), it would cause sufficient refraction to scatter the beam eventually. photons expend no energy to travel, so the room would stay lit up forever. and man, that would have to be some badass 100% reflective material! ;->
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Light is a particle. Wave is its function.
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You are in a 10-foot room with a light in the center.  The photons leave the light, zoom to the wall in 5 nanoseconds, reflect off the wall, and (some of them) zoom into your eye 5 nanoseconds later,  where your brain perceives them about 300 millisconds later.\n\nYou turn off the light.  Generally, the light will cool and stop emitting photons within, say, 100 milliseconds.  But suppose it is a specially-constructed light, and it turns off in 10 picoseconds.  The last photons stream to the wall in 5 nanoseconds, reflect, and hit your eyes 5 nanoseconds later.   Some of the photons that miss your eye may reflect off the walls several times, but there is a 20 to 80% chance of their being absorbed by the paint on the wall each time they reflect.  The brightness in the room therefore decreases a factor of about 2 every 10 nanoseconds.  Within 100 nanoseconds, the number of photons in the room has decreased a factor of about 1000, and it becomes dark.
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well what happens when you shine a light of a specific colour onto a white wall?\n\nOnly the colour that you shined will be reflected back because that is all the wall has to work with!
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You have to remember these are descriptions based on experiments. Light can act as both- as do other particles. Keep in mind that the map is not the territory.....
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y dont u do ur homework urself .ok heres abrief intro.\n\n1.see the level of frequency changes when beam of ultra violet light rays enter to one medium from another medium(to glass from air).\n\n2.when light undergoes refraction it frequency changes its speed acc. to the medium such as(glass,air and water)\n\n3.yes there will be,as light enters to one medium from another medium.
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Turn on the first light switch for a while. Then turn it off and turn the third light switch on, then enter the room. If the light is on, it is the third switch. If the light is off and cold, it is the second switch. If the light is off, but warm, it is the first switch.
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Modern physics is showing that light can actually be both at the same time.  As the quote shows below:\n\n"Light can also behave as a particle and a wave at the same time. An example of light acting as both a particle and a wave is the digital camera---the lens refracts (bends and focusses) waves of light that hit a charge-coupled device (CCD). The photons kick electrons out of the silicon in the CCD. The electrons are detected by electronics that interpret the number of electrons released and their position of release from the silicon to create an image. Another example is when you observe the build-up of the alternating light and dark pattern from diffraction (a wave phenomenon) from light passing through a narrow slit. You see one bright spot (a photon), then another bright spot (another photon), then another... until the diffraction pattern is created from all of the accumulated photons. This happens so quickly that it is undetectable to the human eye."\n\n- http://www.astronomynotes.com/light/s3.htm\n\nThe interesting thing about the duality of light is that it still isn't entirely understood, and the people who understand it don't do a good job explaning.  Here is a link to a website that discuss the experiments which helped discover the wave and particle-like properties of light (and all matter in fact!).\n\nhttp://hyperphysics.phy-astr.gsu.edu/hbase/mod1.html