The Electric Circuit and Its Elements

Simple Electric Circuit

The simplest electric circuit consists of a source of energy, or power source (a primary cell, accumulator, or generator), a receiver of energy (an electric lamp, electric heating device, or electric motor), and two conductors connecting the receiver and power source terminals. The power source (or, for short, the source) transforms mechanical, chemical, terminal, or other energy into electromagnetic energy, which, for brevity, is often simply called electric energy; the energy receiver (or simply receiver), on the contrary, transforms the electric energy to other forms of energy: radiant, thermal, mechanical and so on. The power source together with the conductors and receiver (load) connected to it form a closed loop, along which an uninterrupted stream of electric charges (an electric current) flows. This is called an electric circuit. With respect to the source, the conductors and receiver (load) form so – called external circuit.

The direct cause of flow of electric current in a circuit is the electromotive force (emf) of the power source. Conventionally, the direction of the current in the circuit is taken to coincide with the direction of the emf. The terminal of the sourcethrough which the current “leaves” for the external circuit is called positive (+) and the terminal through which the current enters the source from the external circuit, the negative (-).

Вправа 6. Прочитайте та перекладіть інтернаціоналізми.

Electric, element, energy, accumulator, generator, lamp, motor, transform, thermal, mechanical, electromagnetic, positive, negative.

Вправа 7. Утворіть за допомогою суфікса - ion іменники від дієслів та перекладіть.

To connect, to act, to rotate, to complete, to conduct, to coordinate, to transmit.

Вправа 8. Виберіть правильні твердження.

1. The simplest electric circuit consists of source of energy, a receiver of energy and two conductors. 2. The power source transforms the electric energy into mechanical, chemical, thermal energy. 3. The energy receiver transforms the other forms of energy to the electric energy. 4. The power source, the conductors and receiver form an electric circuit. 5. The power source and receiver form the so – called external circuit. 6. The direction of the current in the circuit doesn’t coincide with the direction of the emf. 7. The terminal of the source through which the current “leaves” for the external circuit is called positive. 8. The terminal through which the current enters the source from the external circuit is called negative.

Вправа 9. Складіть речення з поданих слів і перекладіть їх українською.

1. Is, a, measure, force, of, electromotive, volt.

2. Physicist, a, George, was, Ohm, German.

3. Conductor, is, silver, best, the.

4. Study, we, elements, the, circuit, of, electric.

Вправа 10. Дайте відповіді на питання.

1. What does the simplest electric circuit consist of? 2. What energy does the power source transform mechanical, chemical, thermal energy into? 3. What forms of energy does the receiver transform the electric energy to? 4. What forms an electric circuit? 5. What forms the so – called external circuit? 6. What terminal is called positive (+)? 7. What terminal is called negative (-)?

Вправа 11. Умовні графічні позначення елементів електричного кола.

Виконання вправ на закріплення граматичної теми

Вправа 12. Перекладіть англійські прислів’я з інфінітивом.

1) Live not to eat, but eat to live. 2) Men are not to be measured in inches. 3) Friendship is not to be bought at a fair. 4) It is love that makes the world go round. 5) Treat others as you would like to be treated. 6) It takes two to make a quarrel. 7) It is a woman’s privilege to change her mind.

Вправа 13. Прочитайте та перекладіть фрази видатних людей, зверніть увагу на переклад інфінітиву.

1) It is better to be faithful than famous. (Th. Roosevelt).

2) It is easy to be brave from a safe distance. (Aesop).

3) Better to remain silent and be thought a fool than to speak out and remove all doubt. (A. Lincoln).

Заняття № 30

Тема: Одиниці вимірювання. Закон Ома. Робота і потужність електричного струму

Граматичний матеріал: Об’єктивний інфінітивний комплекс

Вправа 1. Прочитайте та перекладіть лексику за допомогою словника.

primary unit [ˈpraɪˌmeri ˈjuːnit]

сorrelation [ˌkɔrəˈleɪʃən]

determine [dɪˈtə;mən]

electrical state [ɪˈlektrɪkəl ˈsteɪt]

potential difference [pəˈtenʃəl ˈdɪfərns]

pressure [ˈpreʃə]

measure [ˈmeʒə]

resistance [rɪˈzɪstəns]

wire [ˈwaɪə]

supply [səˈplaɪ]

meet the oppression [ˈmiːt ðiː əˈpreʃən]

inversely proportional [ˈɪnˌvərsliprəˈpɔrʃnə1]

cross-section [ˈkrɔs-ˈsekʃən]

mercury column [mərkjəri ˈkɔləm]

amount [əˈmaunt]

constitute [ˈkɔnstəˌtuːt]

appliance [əˈplaɪəns]

kilowatt hours [ˈkɪləˌwɔt ˈauəz]