Post-text exercises. I. Find the Ukrainian equivalents for the following English words and word combinations:

I. Find the Ukrainian equivalents for the following English words and word combinations:

into free space, radio waves, essential properties, direction of travel, wave length, the velocity, relation, distance, the voltage stress, flux, direction, at right angles.

II. Translate into English:

Випромінюється у вільний простір; змінний струм; площина поляризації; короткохвильова довжина; напруга; напрям електростатичних ліній; сила радіохвилі.

III. Fill in the blanks with the following words:

properties, light, magnetic, alternating, velocity

1. Radio waves travel with the …of light. 2. Radio waves consist of ….and electrostatic fields.3. The essential … of a radio wave are the frequency, intensity, direction of travel, and plane of polarization. 4. The quantity 300 000 000 is the velocity of …in meters per second. 5. The radio waves produced by an ….current.

IV. Complete the following sentences, using active vocabulary:

1.Electrical energy that has escaped into free space exists….2.The essential properties of a radio wave are…3.The radio waves produced by….4.The distance occupied by one complete cycle of……5.The strength of a radio wave is measured in…… 6.The direction of the electrostatic lines….

V. Translate the following prepositional word combinations into Ukrainian:

escaped into free space, velocity of light, consist of magnetic fields, direction of travel, plane of polarization, direction of the lines of electromagnetic flux, travels in a direction at right angles, the frequency of the current.

VI. Translate the following definitions and memorize the terms:

Oscillating current. A current that alternately increases and decreases but is not necessarily periodic.

Signal. A visual, audible, or other indication used to convey information.

Automatic system. A system in which the operations are performed by electrically controlled devices without inter­vention of operators.

Radio channel. A band of frequencies of a width suffi­cient to permit its use for radio communication.

VII. Answer the following questions:

1. What does electrical energy that has escaped into free space exists? 2. What is the velocity of these waves? 3. What are the essential properties of a radio wave? 4. Does the wave always travel in a direction at left angles to the wave front? 5. What is the direction of polarization of the wave? 6. What is the velocity of the radio waves? 7. What is the length of a low-frequency wave?

VIII. Speak on different kinds of radio waves and their use in communi­cation.

IX. Translate the following sentences into Ukrainian:

1. We know electric current to be surrounded by a magnetic field. 2. We have seen the existence of life on the earth depend upon the continuous receipt of enormous quantities of energy from the sun. 3. To transmit the human voice around the earth became possible by means of the radio. 4. Air under normal conditions has been found to contain few ions. 5. The radio set may have been plugged in the wrong way, therefore there is nothing happening.6. The engineer wants the new devices to be tested in the laboratory. 7. Radio beacons permit the pilot to find the way in fog or storm.

X. Translate the following sentences paying attention to the Infini­tive and its function:

1. To understand the text you must read it attentively. 2. To make a long story short they repeated the experiment and compared the results. 3. A new machine was invented both to receive and to transmit messages with greater speed. 4. The circuit can be broken to interrupt the flow of electri­city. 5. He stopped there so as to rest a little. 6. You must work hard and systematically in order to master a foreign language in a short time. 7. I don't know him well enough to ask him for help.

XI. Translate the following sentences into the English:

1. Відомо, що кольоровому телебаченню належить майбутнє.2. Кажуть, що наш завод отримав нові електронні прилади. 3. Вважають, що напівпровідники застосовуються все більше в усіх галузях науки. 4. Відомо, що електричний струм оточений магнітним полем. 5. Передача людського голосу стала можлива завдяки радіо. 6. Необхідно, щоб цей прилад був перевірений.