sunofawrx Posted February 5, 2006 Share Posted February 5, 2006 there is no air in space, thus no friction. So if light is thrown off by like a pulsing dying star or a super nova, there should be nothing slowing it down. and what happens when the light hits like(if possible)2x the speed of light. Does it enter a whole diffrent demsion or does it just keep speed ing up? i'd really like to know!~ Link to comment Share on other sites More sharing options...
timo Posted February 5, 2006 Share Posted February 5, 2006 1) To our current knowledge light in vacuum travels at the speed of light (big surprise!), not twice of it or any other value. 2) When you say "keep speeding up" it seems to imply that for some reason you think the light would acelerate. Why so? Objects which do not experience any force (such as friction) keep travelling at the same velocity. Link to comment Share on other sites More sharing options...
entwined Posted February 5, 2006 Share Posted February 5, 2006 It has been said that time must pass for anything to happen. It has also been said that at the speed of light, time ceases to pass-for whatever is going at light speed. Therefore, once a photon achieves light speed does time cease to pass for the photon? And if it does, how can it continue to move? Link to comment Share on other sites More sharing options...
JustStuit Posted February 5, 2006 Share Posted February 5, 2006 Light speed is slower in the atomsphere with the presence of air atoms/molecules, but the speed of light is based off of the speed in a vacuum. In space light travels the speed of light but in air it is slowed from hitting molecuels and travels a *little* slower. Link to comment Share on other sites More sharing options...
sunofawrx Posted February 5, 2006 Author Share Posted February 5, 2006 okay, but in newtons first law an object in motion will stay in motion unless another unless another force oppses it. therefore since there is no force opposing it it should in thoery keep accelerating(or @least thats what ive been told) Link to comment Share on other sites More sharing options...
JustStuit Posted February 5, 2006 Share Posted February 5, 2006 No - this is a misinterpritation of newtons first law. They will remain in motion. They will not accelerate - this involves a force needed. They will remain in motion but not accelerated motion. Newton's second law says that acceleration is directly related to force and inversely related to mass, thus a force is needed. Link to comment Share on other sites More sharing options...
[Tycho?] Posted February 5, 2006 Share Posted February 5, 2006 okay, but in newtons first law an object in motion will stay in motion unless another unless another force oppses it[/i']. therefore since there is no force opposing it it should in thoery keep accelerating(or @least thats what ive been told) Its funny how you quote newtons first law and then make your statement the exact opposite of what the law says. You need a force to accelerate something. No force, no acceleration, no speeding up or slowing down. Things in space will retain a (mostly) constant velocity. You need some external force to cause an acceleration. Link to comment Share on other sites More sharing options...
sunofawrx Posted February 5, 2006 Author Share Posted February 5, 2006 okay but if u give a toy boat a push it reaches T.Velocity then slows down due to friction in space there is no friction so y would it simply reach terminal velocity since there is nothing dtopping it from going faster? Link to comment Share on other sites More sharing options...
JustStuit Posted February 5, 2006 Share Posted February 5, 2006 okay but if u give a toy boat a push it reaches T.Velocity then slows down due to friction in space there is no friction so y would it simply reach terminal velocity since there is nothing dtopping it from going faster? Because it needs a force to go faster - it just won't slow down because there is no force in the opposite direction. Link to comment Share on other sites More sharing options...
5614 Posted February 6, 2006 Share Posted February 6, 2006 When light (a photon) is produced it is travelling at the speed of light. There is no acceleration process. And it never accelerates or decelerates. It always travels at c (speed of light in a vacuum). We know it always travels at c experimentally and mathematically, because of this we can conclude that no net forces act on it. Because there is, as you rightly said, no friction (and there's no net force) there therefore cannot be any driving force. Link to comment Share on other sites More sharing options...
douxt Posted February 8, 2006 Share Posted February 8, 2006 It has been said that time must pass for anything to happen. It has also been said that at the speed of light' date=' time ceases to pass-for whatever is going at light speed. Therefore, once a photon achieves light speed does time cease to pass for the photon? And if it does, how can it continue to move?[/quote'] According to the theory of relativity,time never cease to pass for one object itself, because the relative speed of one object to itself is always zero! Time only does so when something travels at a speed© relatively to you. Link to comment Share on other sites More sharing options...
Daecon Posted February 9, 2006 Share Posted February 9, 2006 A photon that is moving forwrd through space cannot move forward through time. Time and Space have a combined total speed in which matter and energy can pass through tham at. Time passes at a maximum rate for stationary objects and and as you move faster through space, you have to move slower through time to keep this equilibrium in balance. Which is why time slows down as you speed up, and light being the fastest thing that can be, does not experience the passage of time. Conversely, a totally stationary object (which may be by definition impossible when you look at factors of heat from atomic movement and expansion of the Universe) will experience time at the fastest rate, as none of it's total combined space and time amount is being used through motion. Link to comment Share on other sites More sharing options...
alt_f13 Posted February 9, 2006 Share Posted February 9, 2006 I'd like Athiest to answer this for me: If a photon travels for one second towards a mirror, is reflected back, and travels for one more second, isn't its gross velocity then zero? While I can understand why in regards to the large distance travelled, how is this accounted for at the moment of impact with the mirror? In other words, how can light be reflected if it can neither change velocity nor be acted on by another force? Link to comment Share on other sites More sharing options...
Severian Posted February 9, 2006 Share Posted February 9, 2006 I'd like Athiest to answer this for me: I am not Athiest, so I am not sure if I am allowed to respond, but I will anyway. If a photon travels for one second towards a mirror, is reflected back, and travels for one more second, isn't its gross velocity then zero? It average velocity is zero. Its average speed is c (not quite true, since there will be a very small delay at the reflection). While I can understand why in regards to the large distance travelled, how is this accounted for at the moment of impact with the mirror? In other words, how can light be reflected if it can neither change velocity nor be acted on by another force? No one said that light could not change velocity. It cannot change speed. The magnitude of its velocity cannot change but its direction can. So a photon can collide with another particle and gain enough momentum from the collision to change direction (this is in fact the 'force'), but it will leave with speed c again. Link to comment Share on other sites More sharing options...
timo Posted February 9, 2006 Share Posted February 9, 2006 I am not Athiest, so I am not sure if I am allowed to respond, but I will anyway. Nevermind, according to the search button that user doesn´t even exist . Link to comment Share on other sites More sharing options...
Dark Photon Posted February 12, 2006 Share Posted February 12, 2006 light travels at 299,792,458m/s in a vaccum. it cannot go faster because: speed in time + speed in space= 299,792,458 m/s so photons do not get affected by time in a vaccum, and if tehy went waster they would move backwards in time however they are still T=0 old and so they wont get any younger than the birth of the universe. correct me if i am wrong Link to comment Share on other sites More sharing options...
Connor Posted February 12, 2006 Share Posted February 12, 2006 also, when a photon is reflected from a mirror, it is not necessarily (and probably not) the same proton that hit the mirror Link to comment Share on other sites More sharing options...
5614 Posted February 12, 2006 Share Posted February 12, 2006 That is incorrect Connor, but that is because a proton hitting a mirror will not become a photon! Moving on swiftly (or moving swiftly on!) if you take a photon, excite an electron with it, then the electron de-excites itself thus releasing another photon, whilst it is not the actual same photon it is made of the same energy. I don't like the idea of saying "it's not the same photon" or not. Link to comment Share on other sites More sharing options...
Dark Photon Posted February 12, 2006 Share Posted February 12, 2006 see that is a whole new argument. is it the same? would a particle undergoing Bose-Einstein Condensation be the same? is there a mote of absolute energy? and at teh subatomic level, all particles of the same type are congruent Link to comment Share on other sites More sharing options...
Severian Posted February 12, 2006 Share Posted February 12, 2006 also, when a photon is reflected from a mirror, it is not necessarily (and probably not) the same proton that hit the mirror Despite what 5614 said, you are correct. It is most probably absorbed and re-emitted. How you define 'the same' is a but subjective though.... Link to comment Share on other sites More sharing options...
Connor Posted February 13, 2006 Share Posted February 13, 2006 well, I guess it doesn't make sense to make a definition because all photons share the same properties and are indistinguishable from eachother 5614 was just saying a photon doesn't become a proton, via my typo Link to comment Share on other sites More sharing options...
Severian Posted February 13, 2006 Share Posted February 13, 2006 Oh i see - silly me! - i didn't even notice the typo Link to comment Share on other sites More sharing options...
Connor Posted February 13, 2006 Share Posted February 13, 2006 me neither, or I wouldn't have said it Link to comment Share on other sites More sharing options...
Specusci Posted February 13, 2006 Share Posted February 13, 2006 Wouldn't light-speed and a light particle be two different things? If so, couldn't you then somehow accelerate the light particle to such a point that it is faster then the speed of light? Link to comment Share on other sites More sharing options...
Dark Photon Posted February 13, 2006 Share Posted February 13, 2006 unfortunatly, to be at lightspeed you must have either zero mass (like photon) or infinite mass. and if you look at my previous point i explain how things cant go faster Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now