I have been uunable to find out what gives light it's power of speed? Please help! This is driving me crazy!!!

Question

I can't figure out what powers light. I have not read any literature on it. To be honest I wouldn't know where to look. I have asked many of my friends but nobody seems to know. If anyone can help me I would greatly appreciate it. I have had this question for about a year now. I understand where light comes from, but I don't know why it's so fast. Does it ever run out energy? Do the individual light particles keep going forever?

Thank you,

T

Answer 1

Light, although it has no mass, has momentum. It obeys Newton's First Law: Objects at rest tend to stay at rest, and objects in motion tend to stay in motion. Light does not need to be "powered" like a car or a bicycle does, since it does not feel the effect of drag. Once a ray of light is produced, it just keeps going without the need to add additional energy.

Light does need an initial "umph" to get going. This energy is produced when an electron in an atom makes a transition from a high energy state to a low energy state. The change in energy of the electron is converted to a "photon" of light.

In classical physics, light is made of an electric and a magnetic wave. As the electric wave collapses, the magnetic wave grows, and as the magnetic wave collapses, the electric wave grows. It is this process that provides the mechanism for the wave to propagate. Still, this process is self-contained, it does not need to be "powered" by outside energy and it will go on forever unless the light is blocked, and the light-energy converted to other types of energy.

Answer 2

Personally, I gave up on "understanding" physics when I learned that light behaves like a wave or a particle, depending on how you look at it. I do not mean that I gave up on being interested. I just mean that I decided that I would look at the theory as a description of what happens, and not expect to understand the "causes" or "reasons."

But from your question, I get the feeling that you believe that light always moves at "light speed" i.e. "c." This is NOT true. The constant "c" is the limiting speed of light, the fastest it can go. In fact the refraction, or bending of light when it passes through a piece of glass is explained by slowing the light, and the light speeds up again when it leaves the glass.

Also, light gets absorbed by atoms and the atoms can retransmit that energy as heat, or other types of energy.

Truly, if you want a good understanding, you will need to read a college level physics textbook. It would be best if you would read one requiring calculus, because calculus was invented to explain physics.

I would personally not trust a general science textbook. A physics book would be written by someone who is trained in physics, but I don't know what background a person would have to write a general science book.

One presentation on the Theory of Relativity that I enjoyed was in the TV Series "The Ascent of Man" by Jacob Bronowski. This is rather old, but then so am I.

I would look for a physics series produced by Annenberg CPB, or a NOVA program for an "easy" way to learn. There is nothing like learning in "real time" but for precision, you do need to do math.

There are many popular books on physics and they can be entertaining. But you can only get so far without math.

Also, I posted to a question about a spherical mirror recently where I gave some links about optics, which is the study of the reflection and refraction of light.

I hope that you stay interested in this topic.

Answer 3

Subatomic particles, like light particles (also known as photons) got going really fast from the Big Bang. All the energy and motion in the universe stems from the force of A single explosion from a single one dimensional point in space that contained unimaginable energy.Photons tend not to slow down because of the law of inertia, which states that if there is no opposing force (like gravity) to slow you down, then you will keep going the same speed forever. Energy never really "runs out" but gets transferred to other things. Energy cannot be created or destroyed (Einstein's theory).

Answer 4

light particles are given the energy they have from the reactions which create them.

light particles (called photons) are technically massless so when they are created the energy given to them makes them go very fast(at the highest possible speed).

They will not run out of energy unless they are absorbed by something else which is also the only thing which can stop them going on forever.

Interestingly when they pass through any matter their speed is reduced but I am not sure I can explain that phenomenon. I would guess the photons are absorbed and released by the particles they encounter which slows them down.

Answer 5

Photons are quanta of energy or particles of electromagnetic radiation. The electromagnetic spectrum covers everything from radio waves, X-rays, visible light (photons), gamma rays, etc [those are not listed in the order of frequency they should be regarding where they are on a graph of the electromagnetic spectrum!!] Photons are an interesting particle in that they have no mass--unlike a proton or electron or some sub-atomic particle of matter. One source of the electromagnetic quanta labeled photons is fusion reactions inside stars. Another is the heating of the filament of an incandescent light bulb or the stimulation of gases by electric current in a fluorescent light bulb. Photons are the units [or quanta] or maybe "vessels" for the type of energy these reactions or interactions create to be radiated from the sources of these reactions.
Yes, I agree, it's pretty sad I understand what they are and cannot fully explain. I apologise for my lack of eloquence, but I hoped I helped a bit.

Answer 6

Light IS energy, sort of. It actually exhibits properties of both waves and particles. What you have to understand is that things slow down as their kinetic energy changes into other types of energy(usually kinetic energy is transferred into heat energy by friction). Light doesn't lose it's kinetic energy so it doesn't "slow down". There are a few exceptions to this, namely, light being absorbed and traveling through mediums, but generally you can say that it never "runs out of energy(seeing as it is energy)" and keeps going forever.

I hope that helps. Light is a very complex thing to understand. If you want to know more, check out a book on optics, and be prepared for some mind bending information.

Answer 7

light travels in waves... it has its speed because once something in space goes at a speed it continues till another force effects it... the laws of motion

light is emitted by the sun as a result of the sun burning hydrogen into hellium... thats where its power comes from.. and yes light continues forever unless it is effected by something.. it gains that speed because it has no weight and therefore travels at the maximum speed allowed... this is how we see things with the hubble... if light didnt travel that way we wouldnt be able to see galaxies so far away... which we see when they were much younger... we cant see what happens in another galaxy at the moment it happens... rather as long as it takes light to travel that distance.. well that time is how far back in time we are looking.. it is possible that it doesnt work this way.. but then again we arent really sure that everything is relative... its just the accepted theory that seems to explain things... but who knows there is so much left to discover

Answer 8

Random electron motion. Electrons keep repelling off each other which genereates kinetic energy. Hence its power for speed.