Text 1 Washington, the capital of the USA

Washington, the capital of the United States since 1800, is situated on the Potomak River in the District of Columbia. One cannot help mentioning that the terms «Washington» and «District of Columbia» are practically synonymous. The federal district is a piece of land of 26 square kilometres, it is neither in the north nor in the south, it doesn’t belong to any of 50 states of the USA.

The District is named in honour of Columbus, the discoverer of America. The capital owes a great deal to the nation’s first president, George Washington, who succeeded in selecting the site for the District. He laid the cornerstone of the Capitol Building, where Congress meets.

At the beginning of the nineteenth century, the new capital was called «Wilderness City» and the «City of Streets without Houses». It is not the largest city in the United States, for it cannot compare in size with cities like New York, Chicago, Philadelphia, Detroit and Los Angeles, which have more than a million inhabitants. In the political sense, however, it is the centre of the republic and the most important city in the United States.

It’s better to start the sightseeing tour of Washington from Washington Monument, which was constructed in honour of the first American president. Its height is 555 feet (over 180 metres), and from it’s top landing one can enjoy seeing the whole panorama of the city. In the very centre of the city rises the Capitol where the Congress of the Unites States sits. One can see the huge dome of the Capitol from this landing.

Washington is the world largest one-industry town. This industry is government. Straight to the west of the Capitol runs Constitutional Avenue where many departments are situated. The White House, residence of the President, is to the northwest of this avenue. Between the Fourth and Seventh Streets along Constitutional Avenue one can see the building of the National Gallery of Art. It is one of the finest collections of painting in the USA.

Washington has many monuments to American presidents

Lincoln Memorial, Jefferson Memorial, Grant Memorial and many others. The Library of Congress contains millions of books, manuscripts, prints and photos.

Washington avenue are wide and long, most of them being called after states, e.g. Pensylvania Avenue, Massachusetts Avenue. Numbered streets run north and south, lettered streets east and west. The leading universities are Georgetown University and George Washington University.

Across the Potomak River one can see a grey five-sided building. That’s the Pentagon, where the headquarters of the Defence Department are located. It has about 6,500,000 square feet of floor space, three times that of the 102-floor Empire State Building. The Defence Department has become the most important department in the government in number of employees and the amount of money spent. In recent years, its annual budget has averaged more than 60 per cent of all expenditures of the government. The Defence Department has over one million of civilian employers, almost one half of all the national civil servants.

LEXICAL EXERCISES

I. Pronounce these words after the teacher:

Washington [wojingtan], Capitol ['kaepitl], Chicago, Los Angeles, Constitution Avenue, Pentagon, Defence Department, Detroit.

II. Define to what part of speech the derivatives of these words belong and translate them.

to employ — employer - employee — unemployed - employment

to expend - expenditure - expensive — inexpensive -expended

to cover — discover - discovery - discovered — discovering

to select — selected — selection — selective - selector

to compare - comparison — comparable — comparative

III. Put all possible questions to these sentences:

1. The Defence Department has become the most important department in government in number of employees and the amount of money spent. 2. The Defence Department has over one million civilian employees. 3. The annual budget of the Defence Department has averaged more than go per cent of all expenditures of the government.

IV. Answer the questions on the text.

1. Is New York the capital of the United States of America? 2. What state does Washington belong to? 3. Where is Washington situated? 4. Who was George Washington? 5. What can one see from the top landing of the Washington memorial? 6. What building does the US Congress sit in? 7. What does the Washington monument look like? 8. Where is the National Gallery of Art situated? 9. What is the annual budget of the Defence Department?

CONVERSATIONAL PRACTICE

I. Getting Around in Town (in Washington)

— Excuse me, is that the way to George Washington University?

- Yes. Go straight ahead for two blocks and then turn right. You can’t miss it.

- Thank you very much.

- It’s nothing.

— Excuse me, can you tell me the way to Dupont Circle?

- I’m sorry. I’m afraid I can’t help you. I’m new here myself.

- Thank you, anyway.

Characters: policeman, Nick

Just a minute, sir. Didn’t you see that signal?

Yes, I did, officer.

Then why did you cross the street?

There weren’t any cars coming, and 1 thought it was safe.

That doesn’t make any difference. «Don’t walk» means «Don’t walk». Even if there’s no traffic coming.

You’re absolutely right, officer. I know that.

Don’t let it happen again. If you do, you may be fined.

I won’t, officer. You can be sure of that.

— Excuse me. Is there a bus from here to the National Gallery?

No, there isn’t. Take bus 60 to Pensylvania Avenue and then transfer to the R2.

Thank you very much.

It’s nothing.

— Excuse me. Does this bus go to the Library of Congress?

No, this bus won’t take you there. You’ll have to change at Dupont Circle. By the way, you can get there by subway. There’s a subway station over there.

Thank you.

Section 3

Text 2. THE SPEED OF LIGHT

Key terms: speed of light, measured distance, single mirror, multisided mirror, stationary mirror, revolting mirror, telescope, light source, rotational frequency

The first recorded attempt to measure the speed of light took place in the seventeenth century. Galileo tried to measure the time it took for light to travel back and forth between two hilltops about 2 km apart. He stood on one hill at night with a covered lantern while his assistant stood on the other. They attempted to measure the time it took to travel the round trip distance of 4 km, but were unable to do so. Although Galileo increased the distance in subsequent trials, he could not obtain a time measurement. He concluded that either the speed of light is infinite, or it is so great that human reaction does not permit a measurement over such a short distance.

In 1675 Olaus Roemer, a Danish astronomer, attempted to measure the speed of light by observing the eclipse times for Jupiter’s largest moons. This astronomical method gave a value for the speed of light of 2.27x108 m/s.

Armand Fizeau [fizo:], a French physicist, was the first to successfully measure the speed of light by a terrestrial method in 1848. He used a rotating, toothed disc to interrupt the incident light. The disc was placed on one hilltop, and a mirror was placed on another hilltop about 3 km away. Light passed through a gap between two teeth, travelling to the mirror, and was reflected back. If the disk turned fast enough, the returning light passed through the next gap in the disc. From the rotational frequency of the disc and number of gaps around its circumference, he was able to measure the time it took the light to travel 6 km. Fizeau measured the speed of light to be 3.15 x 108 m/s ~ about 5% higher than we now believe it to be, Jean

Foucault [fuko:], another French physicist, replaced the rotating disc with a rotating mirror and obtained a more accurate value.

Albert Michelson, an American scientist, performed Foucalt’s method of measuring the time interval for light to travel a measured distance on Earth. He replaced Foucalt’s single mirror with a multi-sided mirror. Figure 7 shows the apparatus Michelson used.

Octagonal

fig.’7. The apparatus for measuring the speed of light

It consists of an intense light source, an eight-sided rotating merrier, a stationary mirror, and a telescope. The revolting mirror and stationary mirrors were placed on top of two mountains, 35 km apart from each other. Light was directed at one face of the revolting mirror. The light reflected from this face travelled the 70 kvi round trip to the stationary mirror and back. The time for the mirror to rotate through one eight of a revolution was calculated from the rotation period of the mirror. Then the speed of light in air was determined using this time and the 70 km distance. It was found to be 2.99789 x 108 m/s.

Similar experiments were done using an evacuated chamber to measure the speed of light in a vacuum For most calculations, whether for a vacuum or for air, the rounded value for the speed of light с is used. Thus с = 3.00 x 108 m/s. The speed of light in other materials is significantly less.

Vocabulary notes

trial = attempt спроба

lantern [’laentan] ліхтар

subsequent ['sAbsikwant] наступний

circumference [sa'kAmfarans] довжина кола

evacuated chamber вакуумна камера

TASKS

I. Pronounce these word combinations after the speaker and translate them.

Recorded attempt, to travel back and forth, between two hilltops, subsequent trials, human reaction, terrestrial methods, toothed disc, rotational frequency, circumference of a disc, multi-sided mirror, rotating mirror, stationary mirror, rotating period, similar experiments, evacuated chamber, significantly less.

II. Find a synonym (or synonyms) to the first word in each line:

rotate — round, vibrate, move, revolve, improve;

attempt - event, act, perform, trial, vibrate, effort;

travel — go, spread, arrive, move, propagate, cut;

hill - circumference, surface, plane, mountain;

mirror - glass, plate, fork, looking glass, stick;

observe - look, see, hear, watch, investigate, guard;

obtain — go, get, receive, give, translate, write;

place - install, fix, locate, build, distribute.

III. Answer the questions on the text.

1. Who performed the first experiment to measure the speed of light? 2. Did Galileo obtain a time measurement? 3. How did Galileo explain his failure in measuring the speed of light? 4. Who performed the second experiment to measure the speed of light? 5. What method did Olaus Roemer use in his experiment? 6. Who succeeded in measuring the speed of light by a terrestrial method? 7. What was the difference in Fizeau’s and Foucalt’s experiments? 8. What apparatus did Michelson use in his experiment? 9. Is there any difference between the speed of light in air and in other materials?

PROBLEMS

In an experiment similar to that of Michelson’s the correct frequency of a 12-sided mirror is 621 Hz and the distance to the stationary mirror is 20 km. Calculate the speed of light in air from this data.

When walking past a row of shop windows, why can you see yourself in dark windows, but not in brightly lit windows?

Compare and explain the difference in the appearence of stars to astronauts above the Earth’s atmosphere and to astronomers on the surface of the Earth.

If the speed of light in air is 3.00 r 108 m/s, calculate the number of faces on Michelson’s rotating mirror if it has a frequency of 500 Hz and the stationary mirror is 50 km away.

What is the speed of light in a medium if the angle of incidence in air is 50’ and the angle of refraction is 42"?

IV. Read these texts without the dictionary and discuss them with your groupmates.