You will need
- Physics textbook, paper, pencil.
Open a physics textbook on the Chapter on electromagnetic waves. The first difference of electromagnetic waves from the other, which you'll notice is that they propagate in vacuum. That is, electromagnetic waves do not need material medium to propagate.
Remember how in General the wave propagation to understand that allows electromagnetic waves to travel in space without substance. Distribution of any kind of waves means movement in space any disturbance that transmits some parameter of the substance. For example, if we are talking about sound waves, the propagating perturbation is the density of the substance. And any elastic perturbations provides an opportunity to spread in the form of waves it is the fact that there is some space in the center of the disturbance, filled with a substance, which can cause the same outrage. This distinguishes electromagnetic waves.
Note that electromagnetic waves propagate through continuous rebirth electric perturbations in the magnetic. This fact allows electromagnetic waves to propagate from point to point in a vacuum. In other words, the ability of electromagnetic disturbance to travel lies between the electric and magnetic fields. This circumstance is described in the famous Maxwell's equations. Graphically, the electromagnetic wave you can represent mutually perpendicular vectors, each moving along its own plane in a direction perpendicular to both vectors.
Note that perturbation, portable electromagnetic wave is the intensity of the electric and magnetic fields. With the full electromagnetic wave passes these two parameters simultaneously because changes in one begets the other, causing the wave to spread.
Do not forget that the specificity of the electromagnetic wave does not make her exceptional in a number of other waves. An electromagnetic wave, as well as other waves, the characteristic frequency, propagation velocity, period of oscillations, the intensity. And, speaking about intensity, it refers to the mean square value of the electric field and the magnetic field induction.
Note that, despite the lack of a material component in an electromagnetic wave, it can contain arbitrarily high energy. Moreover, unlike other types of waves, energy of electromagnetic waves is greater, the greater the frequency of the wave. This is due to the quantum effects inherent to the electromagnetic wave.