what is electromagnetic waves?why it need medium to travel?Infact why any wave need medium to travel?

Answer 1

Electromagnetic waves are the wave-like component of light. That's the easiest way to put it, because light (electromagnetic radiation) behaves both like a stream of particles and a wave of energy.

Think of it this way: you're standing by a pond of water and throw two stones into it. The ripples from the two stones will intersect each other and either cancel each other out (when a peak meets a trough) or reinforce one another (when a peak meets another peak or two troughs intersect) Light does the same thing: if you shot two lasers so that the lines intersected before being projected onto a screen, you'd see a pattern of light and dark bands showing an interference pattern. So light behaves like a wave.

Yet you've also seen an elevator door that senses if anything's in the way. In basic terms, a beam of light is projected across the doorway and strikes a metal plate, knocking electrons off it and creating a very weak current. When you interrupt the beam with your hand, the current stops and the elevator knows something's in the way. A wave can't really have this effect, so light must behave like a stream of particles.

And this is how the dual nature of light gets around the need for a medium in which to travel. You can shoot a laser into space and it will keep going, even though there is no medium to carry it; it's also why we can still see stars from billions of light years away, because the light continues to travel. A wave of sound, on the other hand is just energy propagating through a medium, just as a wave of energy propagates through water. Sound is just energy, not a stream of particles, and thus must have something to carry it -- that's why you really couldn't hear a spaceship explode in outer space. The energy of the wave is transferred from one molecule of your medium to another, whether it's air, water, or the perilously thin walls of your apartment with the loud tuba player living next door.

Answer 2

Electromagnetic waves are essentially 2 kinds waves that are combined. One would be an electric wave, and the other is a magnetic wave. The best example of an electromagnetic wave is light.

Imagine an electromagnetic wave coming to you. If the electric part of the wave is coming to you vertically, then the magnetic part would be coming horizontally. This is because the 2 parts kind of "create" each other, since a changing magnetic field (the magnetic wave) will create an electric filed (the electric wave), and the other way around.

Electromagnetic waves do NOT need a medium to travel. This is because the 2 parts basically create each other. Both electric and magnetic waves do not need a medium, and so it can travel anywhere it can, even without a medium.

Other kinds waves need a medium to travel. Since a wave is a disturbance, the disturbance can only travel if the material itself is moving back and forth. For example, if a loose rope is made to move in a wave motion, the whole rope is not moving, but the parts of the rope are.

Answer 3

When a charge moves inside a medium ( in this cas a metallic conductor) two fields in space time occur; One is the Electric field ,the other is the magnetic field. so since both field exist simultaneously due the the same phnomena (that is motion of an electron) The mysterious word electromagnetic was coined.
It is only limited to the presence of a mass.With out a mass the electric field or magnetic feld would not exist.
A field can only be formed in a mediun as a function of pressure.
Waves can be formed inside a material.It is the product of oscilliatory motion . So a medium can be any kind of substance.
To understand this requires a good study of what waves are.

Louis De Broglie hit the nail on the head in his dexcription of what constitutes waves.

Answer 4

Light waves do not travel in a medium like sound and water waves. They 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. 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.

Answer 5

Electromagnetic waves do not commute in a medium like sound and water waves. they're the interaction of electric powered and magnetic fields as defined by skill of Maxwell's equations. those equations instruct that a time-various magnetic field creates an electric powered field, and conversely, a time-various electric powered field creates a magnetic field. The equations should be solved to derive the case in which the electric powered fields and magnetic fields decision in this style of way that each and each creates the different in a self-preserving interaction. even as it really is executed, the effect is an equation of a travelling wave that strikes on the speed of one million/sqrt(e0*m0) in free area. e0 and m0 are electric powered houses of area observed as permittivity and permeability. it appears that evidently the speed of sunshine in a vacuum is strictly that value. This effect replaced into the convincing information that undemanding replaced into electromagnetic waves.

Answer 6

People use to believe something called Ether was the medium the EM waves travel through, but debunked long long ago.

Answer 7

E/M waves DON'T need a medium to travel through. If thay did, starlight would never make it to earth, having to travel through the vacuum of space.

All other waves involve the motion of a substance, through which the waves are said to 'travel'

Answer 8

in an electromagnetic wave,an electric and a magnetic field r in 2 perpendicular plains and they propagate in the direction perpendicular to both.
it DOESN'T need a medium to travel.

Answer 9

The medium IS the wave. But here's the kicker: The wave is a particle, too!