The velocity of a light ray moving through a vacuum(space) is 186,000 miles per second. Chinese astronomers observed the light from the supernova,Crab Nebula,in 1054 A.D. How can this problem be worked out using the Distance=rate x time? Also, I would need another way to solve this problem.
206552
the question is impossible to solve with out knowing how far away the nebula is. to find out when the nebula occured you would need to know how far away it is.\nit could be really close and have formed not-so-long ago \nor\nit could be really far away and have formed a long time ago\nfortunately i researched it and the nebula is at a distance of about 6500 ly from Earth\nthe crab nebula was created in 5446 BC \nalso using your \nD=R*T you plug in the Numbers to get a simple algebraic equation:\n6500=186000*T and yout solve for T after converting a few things
318147
Nothing can travel faster than light. Your question is a good one and it relies on a nuance of relativity. Einstein stated that nothing can travel THROUGH space faster than the speed of light. The universe recession speeds have nothing to do with moving through space. We observe the universe receeding because SPACE is expanding faster than the speed of light. It is like a balloon being inflated. Since space itself is not limited by the theory of relativity no contradiction occurs I hope that helped.\n\nTo the person who mentioned black holes, these do not in any way prove that einstein was wrong. Follow me here it may get confusing. Light travels through space at the speed of light. A black hole is an entity so massive that it infinitely warps spacetime. So as light is moving through space it comes to this infinitely deep hole. The light follows the contour of space into the black hole. And because of the extreme force and curvature the light cannot escape.\n\nEinstein has been tested hundreds of times and every time it has stood up to the test. Another key aspect of his theory that you should know that light is not relative. If a car is driving 20 miles per hour and the headlights are on the light goes away from the car at light speed and a person standing on the curb will also see the light moving away at light speed. The speed of light is completely independent of reference point and that is why it makes the ultimate reference point
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a train runs at a speed of 10kmph and u chase it at a speed of 4 kmph , then the speed of the train will appear 10-4=6kmph to u.\n\nbut this is not the case with light rays. u chase it with any speed, its speed will always be 3*10^8 mps\n\nlong ago this boggled the scientists and they came up with relativity theory.\n\nconsider the example given above(train & u)\n\nspecial relativity: \nif both (train & u) r not changing your speeds again and  again then we use special relativity to compare motion between train & u.(ie both are non-accelerared frames)\n\ngeneral relativity\nif either-one/both (train & u) r changing your speeds again and  again then we use general relativity to compare motion between train & u.(ie either-one/both are accelerared frames)
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The speed of light pertains to E&M waves... You can have a wave on a rope for example... it will not be travelling at the speed of light.  To generalize, just state it as 'velocity'\n\nwavelength = velocity/frequency\n\nfor units in this case, x millimeters = (y millimeters/second)/(z cycles/second)
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In metric units, c is exactly 299,792,458 metres per second (1,079,252,848.8 km/h). Note that this speed is a definition, not a measurement, since the fundamental SI unit of length, the metre, has been defined since October 21, 1983 in terms of the speed of light: one metre is the distance light travels in a vacuum in 1/299,792,458 of a second. Converted to imperial units, the speed of light is approximately 186,282.397 miles per second, or 670,616,629.384 miles per hour, or almost one foot per nanosecond.\n\nand everything about speech of light in this site\nhttp://en.wikipedia.org/wiki/Speed_of_light
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HAHAHAH ARE YOU TRYING TO TEST US?\n\nLight is a form of electromagnetic radiation: i.e. it has oscillating electric(E) and magnetic(B) fields that travel through  space at speed c with the same frequency and wavelength.\nrotational energy of light if I am not worng...I like that sh.t!!good question\nRotational energy level gaps typically\n\n \n\nDE = 10^-23 J\n\nTherefore n = 1.5 x 10^10 s^-1
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Cherenkov radiation results from particles traveling faster than the speed of light _in a medium_. The particles are still not traveling faster than THE speed of light, which is more fully described as the speed of light in a vaccuum. Thus, the only implications of this is that the water tanks around nuclear reactors glow blue (which, if you haven't seen it, is really freaking cool).
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It's true that the speed of light is constant no matter what speed at which you or the source is moving.  This is a fundamental postulate of relativity, and there is no explination.  It's just accepted because our experiments indicate that it is true.  You used the formula "lights speed + X = actual speed"  this type of velocity addition is called "Galilean".  It turns out that speeds don't actually add that way.  Far out.\n\nWhere is the rest of the energy? Good question.  The frequency of the light you observe from the sun DOES depend on how fast you and it are moving.  The energy of each photon is given by E = hf, where f is the frequency of light.
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The speed of light is a constant (186,000 mi per second) and does not change based on what it is travelling through.
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Dan's answer is good. Kacey misunderstood the question and then got it wrong to boot; the speed of light is constant only in a vacuum. In materials it is slower, and slower in a prism than in air.\n\nBut you weren't asking about light bending in a prism, were you? You were asking about it bending in space, around a massive body.
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to answer your question it is possible to go faster the the speed of light. The speed of light is 186,000 miles per second.\n\nIf zooming beyond the local speed limit is punishable by law, then some scientists may have a gargantuan speeding ticket to pay. \n\nIn a controversial experiment reported in this weeks journal Nature, scientists at the NEC Research Institute in Princeton, New Jersey claim to have broken the ultimate speed limit -- the speed of light. Though hotly contested, some say this achievement could dramatically increase the speeds at which we can send and receive information. \n\nTaught in physics classes the world over, Albert Einsteins theory of special relativity holds that no object or information can move faster than the speed of light in a vacuum, or 186,000 miles (300,000 kilometers) per second. But NECs Lijun Wang says he created an experiment in which a light beam raced through a gas-filled chamber so quickly, it exceeded the speed of light by a factor of 300. Whats more, the light pulse appears to have left the confines of the chamber before it even entered a seemingly impossible occurrence according to theories of causality, which predict that causes must always precede their effects. \n\n"It sounds crazy, but this can actually occur," said Raymond Chiao, a physicist at the University of California at Berkeley. Chiao, one of a group of researchers who have been working to break the speed-of-light limit, explained that although a common object such as a baseball could never be flung faster than the speed of light, pulses of energy with certain complex properties have been known to bend the rules. \n\n\n\n"It sounds crazy, but it actually can occur." \n\n\n\n\nIn fact, several recent experiments, including one done by Chiao earlier this year, have pointed to energy pulses zooming faster than light speed. Yet each of these experiments has been encumbered by severe limitations on measurement or observation of the energy pulses. In contrast, this latest experiment is being touted by some as the most dramatic example yet of light breaking its own speed barrier. \n\n"The effects are much larger and more spectacular" than previous observations, said Chiao. \n\nIn Wangs experiment, a pulse of light passed through a small chamber filled with atoms of elemental cesium. A light beam traveling through such a medium has two different velocities a velocity for the individual light waves in the beam and a group velocity for the entire beam. Oddly, some light waves in the beam can actually travel backward for miniscule amounts of time, creating a sort of "tail" behind forward-moving waves. As such, a light wave and its tail can leave the gas cavity at different times, creating the effect that the light beam has left the cavity before its even entered. \n\nConfused? Youre not alone. In fact, even scientists who are familiar with this area of study are unsure about the details of Wangs experiment. And many scientists said the experiments results are still open to interpretation. \n\nWilliam Happer, a physicist at Princeton University argued that several specific problems exist with the experiment, including the fact that pulses get distorted when passed through any media other than a vacuum, or empty space. In addition, he said Wang and his colleagues performed the experiment in a way that doesnt tell the whole story, and that it can be interpreted incorrectly. "This is anything but dramatic," said Happer. "If you look at the data, theres essentially no evidence that [the beam] is going faster than the speed of light." \n\nWhats more, most scientists agree that even if such a beam can be proved speedier than light, it would probably not be able to carry any information. Such a feat could conceivably allow data to be sent back in time, thus violating laws of causality and sending quantum physics into disrepair. \n\nOthers are more optimistic as to the possible
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12 hours light distance means: the distance light travels in it for 12 hours.\n\nKnowing that the speed of light is in vacuum 299,792,458 metres per second or 1,079,252,848.8  kilometres per hour, or 186,282 39937/100584 miles per second, or 670,616,629 537/1397 miles per hour. The speed of light through a transparent medium (that is, not in vacuum) is slightly less; the ratio of c to this speed is called the refractive index of the medium.\n\nIf you multiply 1,079,252,848.8  kilometres per hour by 12, you get 1,295,103,418.56 km, a very long distance. If you want to use multiple mirrors to get the "infinite-effect" to "create" this immense distance you need to get a reflection of the sun (with a concave mirror) exactly between the two facing mirrors. Even if you make this happen, remember that the mirror has no memory: when the reflected object is removed from before the mirror, the reflection stops also.\n\nWhy don't you just use regular solar cells that turn solar heat/light into electricity and use a lightbulb after dark?
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In the relativistic limit (i.e. speeds near the speed of light [here denoted "c"]) velocities are not additive in the normal sense.  In particular one must use the relativistic velocity addition rule given by:\n\nv_1 + v_2 / { 1 + (v_1 * v_2 / c^2 ) }\n\nWhere v_1 and v_2 are the speeds of the moving observers.  Notice that when v_1 and v_2 are both siginificantly less than c this reduces to \n\nv_1 + v2, which is what you expect from the everyday world.\n\nIf you plug in .95 c for v_1 and v_2 you obtain that the apparent velocity of the observers to each other is given by:\n\n.998685939553 c or 99.865% of the speed of light.\n\nWhich is how fast they will appear to approach each other from each other's perspective.
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E=mc^2 \nEnergy = mass * (speed of light)^2, c = the speed of light (approx. 186,000 miles per second).
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Wow, great question(s)!  You're brooding over something called the 'twin's paradox', read more about it in the link below.  Basically, what you're fretting over are a couple of the (wierd) implications of special (and general) relativity.  You (and what some others have said) are right, all velocity is relative, which comes from the simple fact that there is no special place that we can call 'still' which we could measure our velocity against.  The single exception to this lies in the speed of light, which is constant for everyone everywhere, no matter what their speed is relative to anything else.  (Note: light isn't special, the only reason it's able to travel at the upper speed limit is because it's particles, photons, have no mass.  Nothing with mass can ever travel AT the speed of light, only near if it is pumped up with huge amounts of energy.)  Think about the wierd implications of this; even if you were able to travel at 99.999999% the speed of light, and your friend would also be able to travel the same speed in the opposite direction, if you shined a light back toward your friend and could measure the photon's speed as they travelled between you the photons would STILL be travelling at the speed of light.  Ok, what does that mean?  The speed of light is just a speed, like any other, but is a constant that can not be exceeded.  Well, like any other speed, c (the usual symbol for the speed of light) is definded as the ratio of the distance travelled (call it 'x') by the time it took to travel it (call it 't'), or c=x/t.  But if 'c' can't change (because it's a constant) what is changing?  There's only two other things in the equation, x (the distance, a measure of space) and t.  Time and space enter into Einstien's equations here, the only way to keep c constant is for x and t to somehow collaborate to change together to make it so.  This is why time (and space) are so 'relavent' to velocity.  And as a matter of fact, time is 'relavent' to gravity as well, as Einstein pointed out so much better than I can.  For Einstein, the breakthrough came when he realized that there is no measurable way to distinguish between gravity and acceleration (a.k.a. the rate of change of velocity with respect to TIME), or more importantly, between the lack of gravity (say a person floating in space) and a particle (or person) in a falling box, they're indistinguishable.  From these two simple ideas (the constancy of c, and the equivalence of gravity and acceleration) Einstein formulated the theory of general relativity, one of the crowning achievements of human thought.  You ask good questions, keep wondering!
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simple explantion (not 100% accurate but it is something you can get your head around easliy)\n\nthe constant thing in the universe is the speed of light. Not time and not distance.\n\nAs you go faster, either time compresses and/or distance compresses. Like a bow wave on a plane or boat. The air/water gets compressed, it doesn't dissapear it just gets squashed a bit because it can not get out of the way of the vehicle fast enough.\n\nSo as you approach the speed of light, space/time gets really compressed, so compared to the rest of space that particular area is really dense. Your region of space/time would appear to be heavier than the rest of space/time, because there is more of it in that region.
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An outside observer would say that the distance between you and the object is increasing at a rate equal to the speed of light, but if the object shone a light at you, that light would still reach you, in the observer's frame.  In the observer's frame, no object is moving faster than light, and there is nothing wrong with the relative separation of objects increasing faster than the speed of light in a frame of reference where both objects are moving.\n\nIn your own frame, you and the object would be moving apart at a relative speed of 0.8c.  Speeds do not add linearly when they are very large.