Notes to the text:

1. Crude devices – найпростіші пристрої

2. photo electricity – фотоелектрика

3. extent – величина, ступінь

4. absorptivity –абсорбційна здатність

5. precautious – передбачливість

6. drops off – зменшуватись

7. opaque – світлонепроникний

8. emitted – виділений

9. prevention – запобігання

10. convection – концепція

11. portable solar heater – переносний сонячний нагрівач

Exercise II

Answer the following questions:

1. In which way dos the sun’s energy manifest itself?

2. Since what time have men tried to use solar energy?

3. What is the most fundamental of all thermal solar processes?

4. What dos the extent of surface temperature rise depend on?

5. Name some of the potential and actual applications of solar energy.

Part 2 Outstanding Scientists and Inventions

1. Alexander Bell - the Inventor of the tTlephone

Alexander Bell never planned to be an inventor. He wanted to be a musician or a teacher of deaf people. In 1863, when Alexander was only 16, he became a teacher in a boys' school in Scotland. But the wish to teach deaf people made him to read books about sound and he started to work on some of his own experiments Reading scientific literature was not easy for him, but he worked hard and learned a lot about the laws of sound. He became interested in the telegraph, and he tried to find a way to send musical sounds through the wires. These experiments were not very successful.

At the age of twenty-five Bell became interested in finding a way to send the human voice through an electric wire. He found an assistant, Tom Watson, who knew a lot about building electric machines. They worked together to build a machine that people could use to talk to one another over long distances.

Two years later when two young people were working on a new transmitter, Alexander spilled some acid on himself. Tom Watson, who was alone in another room, heard a voice. The voice was coming through a wire to a receiver on the table. The voice was Alexander Bell’s! It was saying, “Come here, Mr. Watson. I want you! “ Tom and Alexander realized that their talking machine worked.

The first permanent telephone line was built in Germany in 1847. And in 1878, the first telephone exchange was established in New Jersey. By 1915, a coast-to-coast telephone line was opened in the United States — 5,440 km from New York to San Francisco.

2. Charles Augustin de Coulomb (1736-1806).

1. Coulomb1 a famous French physicist, was a military engineer in his younger days, serving in West Indies for several years, beginning in 1764.There, he supervised the building of fortifications in Martinigue. He returned to Paris in 1776 and grew interested in scientific experimentation. He retired to a small provincial town and got preoccupied2 with research.

2. By 1777 he had made his name as a physicist. In 1777 he invented a torsion balance3 which measured the quantity of a force by the amount of twist4 which it produced in a thin stiff fiber5.Weight is a measure of the force of gravity upon the object, so a torsion balance can be used to measure weight. For this discovery Coulomb was elected to the French Academy in 1781.

3. Coulomb put the delicacy of his instrument at the service6 of electrical experiments. Using small electrically - charged spheres and observing the amount of twist produced on his torsion balance he was able to show in 1785 that the force of electrical attraction or repulsion between two spheres is proportional to the product of the charges on each sphere and inversely proportional to the square of the distance between the spheres, center to center. This meant that electrical forces obeyed a rule similar to the law of gravitational forces as worked out by Newton. This is called Coulomb's law. In his honor an accepted unit for quantity of electric charge is the coulomb.

Notes

1. Coulomb – Кулон

2. to get preoccupied – зайнятися будь-чим

З. а torsion balance – крутильні ваги

4. the amount of twist – кількість крутіння

5. a thin stiff fiber – тонка туга нитка

6. to put the delicacy of ... аt the service ... – використовувати чутливість…для…