2006-06-30 16:23:01 · 8 answers · asked by steven a 2 in Science & Mathematics ➔ Physics
A very good question. Newton pondered the same thing about gravity. The smallest denominator of light is the photon. Photons are waves and they are particles (particle/wave duality -- quantum physics). It depends on what you look for. If you look for a particle, you get a particle. If you look for a wave pattern, you get a wave pattern. Either way, these bundles of light zip along at 186,000 miles per second in empty space. They never slow down, they never speed up, and they do not move through time, as they have hit the cosmic speed limit and all their motion through time is diverted by their motion through space. If you could travel at near light speed, I'm sure you've heard that time slows down for you relative to your friend back on Earth. It may seem like a day to you, but your friend, when you get back, is 50 years older. Anyhow, to answer your question, a space ship can travel through empty space, it doesn't need a medium - it keeps on going from that initial acceleration. Once it is beyond the influence of Earth's gravity, it keeps on going, it never slows down, unless it enters another gravity well, fires its retro-rockets, or hits something. At lightspeed, you have all the energy you need to keep on going forever, until you hit an atom. The atom absorbs the photon and gets all excited and the atom's electrons do a little quantum jump to a higher permitted electron orbital state. When the atom settles down again, it emits -- you guessed it -- a photon, and the photon goes on its merry way.
2006-06-30 16:54:00 · answer #1 · answered by Anonymous · 1⤊ 0⤋
Light being an electromagnetic wave can travel without a medium as it's movement is based on changing electric and magnetic fields nd not on the presence or absence of medium.
2006-06-30 16:42:09 · answer #2 · answered by kshitiz 1 · 0⤊ 0⤋
But it does travel through a medium.
Open air, space, whatever. The universe is filled with a wide variety of particles and waves that light reacts upon as it travels from it's source.
2006-06-30 16:29:57 · answer #3 · answered by lowflyer1 5 · 0⤊ 0⤋
Suppose, we have two charged parallel plates (one positively charged and the other negatively charged) kept in VACUUM.
There is electro static field between them. If we vary the charge in one plate then the charge in the other plate is affected.
If the distance (in vacuum) between the plates is 3x10^8 m, then the interaction will take place after one second.
Similarly magnetic fields are also travel in vacuum with this speed.
Light is a combination of electric and magnetic fields. Hence they can travel even in vacuum.
2006-06-30 16:39:43 · answer #4 · answered by Pearlsawme 7 · 0⤊ 0⤋
Your ? brings to mind the 'ether' theory that was debunked around 1900 but belived by most of the world's physicists because their only other experience with waves was sound, which definitely requires a medium.
2006-06-30 16:30:23 · answer #5 · answered by Steve 7 · 0⤊ 0⤋
nicely it relies upon on the perspective of prevalence. if the perspective of prevalence is ninety. then the replace in medium received't result the direction of light and the mild will flow instantly contained in the subsequent medium. yet when the perspective of prevalence is lower than ninety then then mild will refract (there'll be a replace in direction) and assorted the mild will mirror back. so it potential stepping right into a lot less mild contained in the subsequent medium.
2016-10-14 00:36:36 · answer #6 · answered by ? 4 · 0⤊ 0⤋
because light in itself is something wehre as sound waves are nothing. light is something so it can go where it damn well pleases
2006-06-30 16:28:13 · answer #7 · answered by xirekaj 3 · 0⤊ 0⤋
Because, as an electromagnetic "wavicle", it is its own medium.
2006-06-30 16:27:04 · answer #8 · answered by Dave_Stark 7 · 0⤊ 0⤋