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English for Telecommunications and Radio Technologies in Rail Transport.docx
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The properties of electromagnetic waves

1. Discuss the general knowledge questions connected with the topic of the unit:

  1. What scientists studied the phenomenon of electromagnetic waves?

  2. What properties of electromagnetic waves could you name?

  3. What areas are the electromagnetic waves used in?

  4. What other types of waves could you list? What is their application?

2. Read the words and learn them by heart:

Amplify (v) – усиливать

Angle (n) – угол

Charge (n) – заряд

Current (n) – ток

Diffraction (n) – преломление

Emitter (n) – излучатель

Field (n) – поле

Generator (n) –генератор

Interference (n) – интерференция

Medium (n) – проводник, среда

Obstacle (n) – препятствие

Oscillate (v) – вибрировать, генерировать

Property (n) – свойство

Receiver (n) – приемник

Reflection (n) – отражение

Refraction (n) – преломление

Source (n) – источник

Substantiate (v) – доказывать

Value (n) – ценность

Variety (n) – разнообразие

Velocity (n) – скорость

3. Read the first part of the text «Properties of Electromagnetic Waves» and translate it using the words from exercise 2. The properties of electromagnetic waves

In 1865 the famous English physicist Maxwell, based on the results of Faraday's work on the study of the electromagnetic field, was able to theoretically substantiate the possibility of the existence of such fields in the absence of currents and charges that generated them. The field configuration outside the source is a wave. Studying the properties of electromagnetic waves, it is impossible not to notice an interesting fact: the propagation velocity depends on the medium. For example, in a vacuum it is about 300 thousand km / s. Since this value corresponds to the speed of light, it allowed Maxwell to assume that light is one of the varieties of electromagnetic waves. Later this was confirmed by the Hertz’s experiments. In fact, the properties of waves depend on their length. The whole spectrum was conditionally divided into areas, each of which has its own manifestations.

The properties of electromagnetic waves are unique, since their general interaction with matter is explained at once by two components - magnetic and electrical. Thus, in an electromagnetic wave that is not subjected to an external action, both fields oscillate in their directions and planes, perpendicular to the propagation direction of the wave itself. The basic properties of electromagnetic waves are represented by a variety of manifestations, regardless of the nature of the source. Let's consider some of them. It is much more convenient to represent real experience, so we will mentally use two devices - a radio wave directional radiation generator and a receiver. As already indicated, the results obtained are applicable to any type of wave. Knowing the properties of electromagnetic waves, they can be controlled by the special method.

https://www.toppr.com/guides/physics/communication-systems/propagation-of-electromagnetic-waves/