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LEAVING EXAM QUESTION: SCIENCE AND TECHNOLOGY

Science and technology is as old as the mankind. Since the existence of man, science has been developing as people have sought to somehow improve their lives. The first inventions and discoveries were very simple. As the first important discovery in the development of mankind we consider the discovery of fire. On the other hand the first important invention was the invention of wheel. About the year 3,000 BC people started to live in towns, where science began to grow. Many important inventions like writing, reading, counting, astronomy, medicine and chemistry began to develop. Man looked at stars, the Sun and the Moon, and they helped him e.g. to measure time. Man˘s effort to survive and to improve his way of life made him invent new and better tools, get deeper knowledge and control of the forces of nature. As man˘s knowledge grew people found it useful to classify it. It was separated into various branches, such as physics – the study of natural forces, biology – the study of living beings, chemistry – the study of materials.

Watching the flight of birds man wanted to fly too, so he tried to imitate them. This dream was realised in the twentieth century. Science and technology is strongly connected with space flights and space observing. On the 4th of October 1957 the Sovyet Union launched the first satellite called Sputnik. It was a sphere about 58 cm in diameter and weighed 83 kg. It was carrying scientific instruments but no crew. A month later the second Sputnik carried the first space traveller – a dog named Laika. The world˘s first astronaut was Yuri Gagarin( 12th April 1961 ). He made only one orbit of the Earth and landed again safely. The American astronauts Neil Armstrong and Edwin Aldrin were the first people who landed on the Moon( 21st july 1969 ).Then other space flights followed, scientists prepared long space voyagers, many space stations have been built, thousands of satellites are orbiting our planet for communication purposes, weather forecast etc. Space flights bring us a lot of useful things, but there are also disadvantages of them.

Advantages: we gain new knowledge about the universe, possibilities of using space supplies of raw materials; satellites in orbit can improve TV signals and there is better communication between people; also we can find the places with similar living conditions as on the Earth.

Disadvanteges: it is necessary to decrease the money that goes into the space flights because some of this money is needed to solve hunger, poverty and other problems on the Earth. Rocket fuels damage the atmosphere, using satellites and rockets can be misused for military purposes, and there is a danger for astronauts because they have to overcome extreme conditions.

The human body in space:

Artificial satellites are of many different shapes and sizes and are sent into orbit for several different reasons. They usually have solar cells to use the energy from the Sun for their instruments and to keep them on the correct course. A common use for satellites is to improve international communications. Communications satellites can pick up signals from a point on the Earth and relay them to the other side of the Earth by amplifying them and then beaming down to a ground station. Some satellites carry cameras which take pictures of the Earth˘s surface to help meteorologists forecast, and the weather map – makers to make accurate maps. Other satellites carry cameras and telescopes which are pointed out into space so that astronauts can get more information about distant stars and planets.

There are many problems in the world and science must help to solve them. The first of them is the environment. The steep development of industry in the last 50 years is a great danger for life on the Earth. There are two pressing problems with the atmosphere of our planet which are caused by emitting polluting materials into the air. The most pressing problem is caused by the impairment of the ozone layer in the stratosphere of the Earth. Ozone is decomposed by freons above all. The second great problem is the green-house effect which is caused by a lot of CO2 in the air. The increasing of temperature can cause thawing of polar icebergs maybe in a period of 50 years. Scientists must solve the problem of checking the consequences of these processes, e. g. the problem of settlements on the coast endangered by the sea level going up. Another problem is the problem of energy. We need energy to keep the development of industry.

There have been invented three types of power stations: 1.Thermal power stations - pollute the air, release smog, oxid of sulphur and carbon, 2.Water power stations - destroy the landscape,there are not many rivers suitable for it and 3.Nuclear power stations - produce a lot of waste materials.

Some biological experiments can be conducted in space to learn something about whether micro-organisms can live in the hard space conditions. If we explore space, we must try to find some forms of life there. Some micro- organism could be on Mars. Biologists could examine them and compare them with those on the Earth to understand the causes of some virus diseases. It can

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V.ZUBEREC, B.SIMOVA


also help us to learn something more about the origin and the evolution of life on the Earth. The more we know about space, the more we know about the Earth because this planet and everything on it is a part of space.

Some of the most important inventions and discoveries:

Electricity – we can not imagine our life without electricity; we use it for lighting, heating, radio, TV, etc.

It all started in about 600 BC when the Greek philosopher Thales noticed that amber rubbed with wool attracts light objects( as feather, straw ). Electricity which is used as a form of energy is in fact electric current. It is produced in power stations by generators and comes into our houses via cables.

Paper – before it was invented people wrote on anything, e.g. clay, tablets, silk, palm leaves, later papyrus. Paper was invented in China in 105 AD. The first chinese paper was made of silk, then hemp and the bark of mulberry trees. Today most paper is produced by the chemical treatment of wood pulp.

The telephone – it enables us to communicate with others both in everyday life and in business. It dates back to 1876 when Alexander Graham Bell, physicist and inventor, developed his “speaking box “. Another important name in the field of communication is Gugliemo Marconi, an italian electric engineer, who began radio experiments in 1894, and 4 years later he carried out the first international( England – France )wireless transmission.

Television – is a relatively recent achievement, at least for the public, because it did not appear in people˘s houses until the 1950s. But for experts television as a means of transmitting pictures has existed longer. The first television transmissions were made in England in 1926 by the Scotsman John Logie Baird.

Laser – in 1961 it was discovered that when certain substances were exposed to light at a particular frequency they emitted a beam of light at the same frequency but with far great power. When the materials used are glass or crystal, this light is known as laser light. Laser light can be transmitted over long distances in a highly concentrated beam which has a great deal of energy. Laser is used in industry for cutting, drilling or welding very hard materials, in space navigation it is used for maintaining communication and measuring distances and it is also used in medicine in many kinds of operations – the most common medical use is in eye surgery.

Famos scientists

JAMES WATT – a Scottish engineer who made very important improvements to the steam engine. He established the first factory for the steam engines production.

MICHAL FARADAY – a physicist and chemist who advanced in work of Humphry Davy the physicist

ALEXANDER FLEMING – a physician, microbiologist and bacteriologist. He discovered penicilin. The Nobel Prize for Medicine was awarded to him.

ERNEST RUTHERFORD – a physicist who worked in the field of the atom structure. The Nobel Prize for chemistry was awarded to him.

CHARLES DARWIN – natural historian and developer of the evolution theory. This theory was the most important single scientific innovation of the 19th century. It marked the beginning of a new period in the development of biology.

ISAAC NEWTON – a mathematician, physicist and astronomer who completed the findings of Johannes Kepler and Galileo Galilei.

THOMAS ALVA EDISON – inventor; the most important invention of Edison is the electric bulb. It was the phonograph that was made in 1877.

ALBERT EINSTEIN – physicist and founder of the Theory of Relativity. This theory shook the whole scientific and intellectual world.

DMITRI IVANOVICH MENDELEYEV – his name is best known for his work on the periodic law. He arranged the chemical elements in the periodic table according to their atomic weights and predicted the existence of the elements gallium, scandium and germanium before their discovery. The Davy medal of the Royal Society was awarded to him in 1882.

ALFRED BERNHARD NOBEL – chemist, engineer, industrialist. He invented Dynamite and other powerful explosives. He is known above all as the founder of the Nobel Prize. It is awarded to those who, during the preceding years, had conferred the greatest benefit on mankind in the field of physics, chemistry, psychology, medicine, literature and peace. The prizes are paid by Nobel˘s will. The distribution was begun on December 10, 1901, the 5th anniversary of the death of the founder. The Prize for Economics in Memory of Alfred Nobel was established in 1968. The Peace Prize is presented in Oslo, the other prizes in Stockholm. The Nobel Prize is either given entirely to one person or shared between two or three persons. Prizes are not awarded when no worthy candidate in the meaning of Alfred Nobel˘s will can be found.

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