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Text 9A Descending to New Ocean Depths

The text gives information on some types of advanced manned submersibles. A submersible is a small , mobile undersea research vessel capable to function in the ocean depths. Submersibles are constructed in various sizes and shapes. They can be used for laying pipelines underwater, for seafloor mapping, for making direct observations and measurements, recovering lost equipment, for possible rescue activity and so on.

Speaking about the shape of a new submersible Id like to describe one of them. It has a spherical transparent plastic hull mounted on a metal platform that makes it look like underwater helicopter. Due to the cycloid rotor the helicopter can maneuver itself in the water like a sports car.

It is pointed out that this model has a mechanical hand called a sensory manipulator system. This system is provided with miniature video cameras and the microphones which enable the submersible to hear and see the marine life.

Nowadays the scientists are working over the project of the worlds deepest submersible. It will be capable to submerge up to 21,000 feet. The ship will be driven by a battery-operated electric motor and stay under water up to 9 hours. This craft will be provided with colour video cameras and will collect samples by manipulating 2 robotic arms.

In conclusion I want to say that Russian, French, Japanese and American scientists and engineers are developing crafts which can submerge deeper, stay longer and perform difficult underwater tasks with extreme precision. If such crafts are constructed on a large scale many people will get the opportunity not only spend their holidays under water but grow and cultivate sea plants, fish and pearls.



Text 10A Laser

The text gives some information on laser. Laser is one of the most sophisticated inventions of man. It is a device which produces an intensive beam of light of a very pure single colour. The name laser stands for Light Amplification by Stimulated Emission of Radiation. The strength of a laser is so great that it can vaporize the hardest and most heat resistant materials. It can make lead run like water. Laser beam can be focused so precisely that it can destroy a single cell of living tissue.

Laser can be used in industry for cutting and piercing very hard materials such as metals, bricks, granite and even diamonds. It can also be used in surgery for making bloodless incisions, particularly on the retina. But the most important use of laser is in telecommunications. It is used for recording, processing and transmitting large amounts of information. Laser beam vibrates billons of times faster than ordinary radio waves, so it could carry radio, TV and telephone messages all over the world simultaneously. For example, a laser beam can transmit the whole text of Encyclopedia Britannica just in a few seconds.

There are different projects to use laser in science and industry. Nowadays scientists in different countries are working on a very interesting problem: combining laser and thermonuclear reaction for producing practically limitless source of energy. There is also an idea to use laser for solving the problem of controlled thermonuclear reaction. As far as I know there are projects to use laser for long distance communication and for transmitting energy to space stations and to other planets of solar system.

In conclusion Id like to say that these projects have not been realized yet because of great technological difficulties and great cost involved, but Im absolutely sure that in time these projects will be realized and laser beam will become one of the main technological tools.


Date: 2015-12-17; view: 977

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