Why do electromagnetic waves travel?

Electromagnetic waves are a form of motion in an electromagnetic field. Electricity and magnetism can be said to be two sides of the same coin, a changing electric field will produce a magnetic field (i.e., an electric current will produce a magnetic field), and a changing magnetic field will produce an electric field. The changing electric field and the changing magnetic field constitute an inseparable unified field, which is the electromagnetic field, and the propagation of the changing electromagnetic field in space forms electromagnetic waves, and the changes in electromagnetism are like water waves generated by the breeze on the water surface, so they are called electromagnetic waves, also known as radio waves.

The media involved in the propagation of radio waves include the earth (underground, underwater, and on the surface of the earth, etc.), the earth's atmosphere (troposphere, ionosphere, magnetosphere, etc.), solar-terrestrial space, and interstellar space. Most of these media exist in nature, but there are also many artificially generated media, such as rocket flame plasma and plasma produced by aircraft re-entering the atmosphere, which are also the subject of research on radio wave propagation. The structure of these media varies widely, and their electrical properties vary.

However, in terms of its role in the propagation process, it can be divided into three types: continuous (uniform or inhomogeneous) propagation medium, such as troposphere and ionosphere; interfaces (rough or smooth) between media, such as sea and ground, etc.; Discrete scatterers such as raindrops, snow, airplanes, missiles, etc., which can be individual or swarm. Most of the properties of these media change randomly over time and space.

Thus the amplitude and phase of the waves interacting with it also vary randomly with time and space. Therefore, the properties of the medium and propagating waves need to be described statistically.

Ternary Equilibrium Law 5-10 Characteristics of Electromagnetic Wave Propagation and the Nature of Hubble Redshift.

Electromagnetic oscillation produces electromagnetic waves, for example, the signal generated by the high-frequency oscillation circuit is an electromagnetic wave, which can be emitted through the antenna, and obviously its energy comes from the power supply of this circuit; Hertz discovered that the high voltage used in the experiment of electromagnetic waves caused the electric sparks between the spark gaps is a method of generating electromagnetic oscillations, and its energy is also from the power supply of the device.

There are many forms of electromagnetic wave propagation, mainly space propagation and duct propagation of waveguide system. The microwave used in wireless communication (such as mobile phone) is transmitted between the base station and the mobile phone in space, and after entering the mobile phone, it is the waveguide propagation, and in general, the distance of wireless transmission is much greater than the transmission distance in the pilot system as a feeder. Electromagnetic waves propagate forward through a constant transition between electric and magnetic field energy (the law of which is determined by Maxwell's equations) and can propagate forward without loss in a vacuum, without the need for a medium or a so-called etheric substance as its propagation medium.

The propagation principle of electromagnetic waves is described by Maxwell's equations. Maxwell's equations are the fundamental laws of electromagnetism, and it consists of four equations, which are Gauss's law, Faraday's law, Ampère's law, and Faraday's law of electromagnetic induction.

According to Maxwell's equations, electromagnetic waves are oscillating fluctuations formed by the coupling of changing electric and magnetic fields. When there is a change in electric current or charge, a changing electric and magnetic field is generated. These varying electric and magnetic fields interact to form electromagnetic waves.

When electromagnetic waves propagate in space, they propagate at the speed of light (about 300,000,000 meters and seconds) and the speed does not change when propagating in a vacuum. It can propagate in various mediums such as air, water, metal, etc., but the propagation speed in the medium is slower than in the vacuum, which is due to the response and interaction of the medium to electromagnetic waves.

The propagation of electromagnetic waves is the transmission of good energy and information through the interaction of electric and magnetic fields. When an electromagnetic wave propagates to a target receiver, the receiver senses a changing electric and magnetic field, which converts the electromagnetic wave into an electrical signal for transmission and processing.

The propagation of electromagnetic waves has the dual characteristics of wave and particle, which can be explained by both wave theory and particle theory. According to quantum mechanics, electromagnetic waves can be seen as the flow of particles composed of photons. This dual nature gives electromagnetic waves properties such as the energy of particles and the amplitude and frequency of fluctuations.

Electromagnetic waves can travel in a vacuum. There are many kinds of electromagnetic waves, such as radio waves, infrared rays, light waves, lasers, ultraviolet rays, X-rays, radiation, etc., which are all electromagnetic waves, but the wavelengths are different. Electromagnetic waves can travel in a vacuum at almost the same speed, 300,000 kilometers per second.

Radio and television are conducted using electromagnetic waves. In radio broadcasting, sound signals are converted into electrical signals, which are then carried out into the surrounding space by electromagnetic waves that oscillate at high frequencies. In another location, people use receivers to receive these electromagnetic waves and then restore the electrical signals into sound signals, which is the general process of wireless broadcasting.

In Lingze TV, in addition to processing sound signals like in wireless broadcasting, the optical signal of the image should be converted into an electrical signal, and then these two signals will be transmitted to the surrounding space by the electromagnetic waves of high-frequency oscillation, and the TV receiver receives these electromagnetic waves and restores the electrical signals into sound signals and optical signals, so as to show the picture of the TV and the sound in the speaker.

The electric or magnetic field of electromagnetic waves varies with time and is periodic. The distance traveled in an oscillation period is called the wavelength, and the reciprocal of the oscillation period is the number of vibrations per second, which is called the frequency.

How electromagnetic waves are emitted from the antenna.

The changing electric field produces a magnetic field, and the changing magnetic field produces an electric field, and so on and so on and so on propagates to the surroundings. It does not require any medium, it can propagate in a vacuum, and all the energy comes from the emission source.

Just like light, electromagnetic waves and light are both very small particles, with wave-particle duality, visible light and electromagnetic waves have different frequencies, and if you are specifically interested, you can look at a brief history of time.