Контрольная работа 6 Вариант 3
Дата сдачи: Апрель 2012
I. Перепишите и письменно переведите текст.
The Promising Field of High-Pressure Research
Subjecting materials to high pressure greatly changes their properties. When compressed under more that 500.000 pounds per square inch ordinary liquids become solids. Gases become liquids. Some rocks stretch like rubber. Insulating materials begin to conduct electricity. Water freezes at room temperature into dense heavy cubes which explode violently when the pressure is suddenly released.
The most interesting discovery in connection with high-pressure research is the artificial conversion of graphite to diamonds.
The interior of the earth itself is a high-pressure laboratory. The pressure at the centre of the earth is estimated to be 3.000 kilobars.1 Graphite subjected to the tremendous heat and pressure generated deep below the earth's surface turns to diamond in the course of thousands or, perhaps, millions of years. Today total output of synthetic diamonds in the world amounts to several tons annually.
Metals become increasingly conductive under high pressures. This has led some scientists to suggest that increasingly high pressures might cause some metals to become superconductive at room temperature. Superconductivity, the complete absence of electrical resistance, has numerous potential scientific applications, but can now be obtained only at extremely low temperatures close to absolute zero.
II. Перепишите вопросы к тексту и письменно ответьте на них. Переведите вопросы и ответы на русский язык.
1. What influence has high pressure on:
в) insulating materials?
2. What is the pressure at the centre of the earth?
3. What is superconductivity?