I clearly am misunderstanding a fundamental principal here. As far as I know sound needs a medium such as air or water to travel. While light only gets distorted by traveling though something. Yet I know that communication is space is possible.
So is it that the signal of radio is more like light than sound in that it needs no medium or am I completely lost on this concept?
2006-11-06 17:56:00 · 8 answers · asked by Gamla Joe 7 in Science & Mathematics ➔ Physics
thanks guys that cleared up somethings. I still have one or two questions but I will ask those at another time.
2006-11-06 19:06:31 · update #1
Electromagnetic waves don't need medium to travel.
Like light, radio too, is an elctromagnetic wave, so it can travel through vacuum.
2006-11-06 17:58:24 · answer #1 · answered by Anonymous · 1⤊ 0⤋
Light waves and radio waves are the interaction of electric and magnetic fields as described by Maxwell's equations. These equations show that a time-varying magnetic field creates an electric field, and conversely, a time-varying electric field creates a magnetic field. The equations can be solved to derive the case in which the electric fields and magnetic fields vary in such a way that each creates the other in a self-sustaining interaction. When this is done, the result is an equation of a travelling wave that moves at the speed of 1/sqrt(e0*m0) in free space (a vacuum). e0 and m0 are electrical properties of space called permitivity and permeability. it turns out that the speed of light in a vacuum is exactly that value. This result was the convincing proof that light was electromagnetic waves. Since electric and magnetic fields can exist in a vacuum, light and radio waves can travel through a vacuum.
2006-11-07 02:50:33 · answer #2 · answered by gp4rts 7 · 1⤊ 1⤋
A very good question that physicists were wondering about up to the end of the 19th century. Then Michelson and Morley did an experiment to see if the speed of light changed when measured going in different directions, which it would if it were traveling thru a medium as sound does thru air. This predicted medium which filled all of space was called the "ether" and was thought to be necessary for light to travel. If it was found to be real it would also provide an "absolute" frame of reference for all celestial objects, so many scientists dearly wanted it to be real.
Michelson and Morley, however, found no difference at all in the speed of light no matter what direction it was measured from (they had mirrors on a rotating table to do this). They ran their experiment at different times of year when their laboratory would be at a different angle relative to outer space as the earth orbited the sun, but they never found any difference in the speed of light, whether in direction or by how fast the table was turning!
This result was completely unexpected and created a crisis in physics, but they had to accept the results of their experiment. It took a 26-year-old patent clerk named Einstein to turn this information into a new field of physics called relativity in 1905.
2006-11-07 03:08:58 · answer #3 · answered by hznfrst 6 · 1⤊ 1⤋
Think of a wave a disturbance and the trend to travel. It needs a medium to do so since it will have to interact. Exchange energy and propagate likewise.
Now as far as light or any nature of electromagnetic waves are concerned the medium is not only unnecessary it is also a hazard for them since it absorbs their energy. Now the dual nature of the waves is what makes them special. Their vector of propagation is favored due to the constant transition of electric and magnetic waves. And this trend to change and exchange energy that “helps” it to travel. The wave constantly changes field vector in nature magnitude and direction.
So exactly opposite to the mechanism of propagation of mechanical waves the electromagnetic waves do not need a medium to interact and change / ex-change energy.
2006-11-07 06:52:55 · answer #4 · answered by Emmanuel P 3 · 0⤊ 1⤋
You are absolutely right. Radiowaves are part of the light spectrum. Check any light spectrum chart and you will see that am and fm radio waves are also light light waves along with color, ultraviolet, and infrared light. What confuses many people is that not all light is visible to the eye. When communication through light waves is done, the audible signal is converted into a light signal when sent and back into an audio signal when received. I know this answer is general, but its a start. Hopefully it helps you know where to look.
2006-11-07 02:15:54 · answer #5 · answered by big mix 1 · 1⤊ 1⤋
yes...
radio wave is not same as sound wave.
sound wave need a medium to travel.
but, radio wave is a type of ELECTROMAGNETIC WAVE
electromagnetic wave can pass through anythings without needing any medium. so electromagnetic wave can pass through vacuum also...
hence, radio wave also can pass through a vacuum.
other examples of electromagnetic wave is infrared, uv light, visible light, X-rays, gamma rays etc.
2006-11-07 06:28:39 · answer #6 · answered by edison yan 1 · 0⤊ 1⤋
well radio wave is not like a sound wave it is a electromagnetic wave(like a light wave) where as sound is a longitudinal wave....the e.m .waves dont need medium to travel....
they have electric and magnetic fields perpendicular to each other and hence help in propagation of wave...where as longitudinal wves need a medium...
2006-11-07 02:06:30 · answer #7 · answered by indurti karthik 2 · 1⤊ 1⤋
as explained electromagnetic waves travel everywhere
2006-11-07 05:08:16 · answer #8 · answered by sudhan 2 · 0⤊ 1⤋