VIII. Language.
Exercise 16.
a) Find in the text sentences about the role of electricity for the engineering process and technology.
b) Find in the text sentences telling about the use of electricity in the solution of mathematical problems.
IX. Oral Practice.
Exercise 17. Give your own examples of the so-called “routine brain work”.
Exercise 18. Suggest some other title of the text.
Exercise 19. Suggest subtitles to each paragraph of the text.
Exercise 20. Express the main idea of the text in the shortest possible way.
X. Reading.
Exercise 21. Skim the text C.
Text C.
Electric Fields
If two charges particles come close to each other, they will experience a force. If the two particles are alike in charge, the force will be one of repulsion. If the two particles are opposite in charge, the force will be one of attraction. The repulsion and attraction of particles occurs because charged particles have electric fields around them.
An electric field is the region surrounding a charged particle in which an electric force affecting other charged particles is noticeable. The electric field is strongest near the charged particle. It is weakest far away from the charged particle. The strength of an electric field depends upon the distance from the charged particle. As the distance from a charged particle increases, the strength of the electric field decreases.
XI. Comprehension.
Exercise 22. Agree or disagree.
1. If two charges particles come close to each other, they will experience a force.
2. If two charges particles are opposite in charge, the force will be one of repulsion.
3. An electric force affecting other charges particles is unnoticeable.
4. The electric field is not so strong near the charged particle.
5. The strength of an electric field depends upon the distance from the charged particle.
XII. Language.
Exercise 23. Give definition of an electric field.
XIII. Oral Practice.
Exercise 24. Explain what will happen if two charged particles come close to each other.
Exercise 25. Tell about electric fields.
Supplementary Texts
After you have read the texts answer the following questions.
Try to express your answer in your own words if possible.
Non-traditional sources of energy
B
iomass:
We
are fortunate in the United States and around the world to have large
resources of organic material, called biomass. In the long run the
most effective way to use biomass is likely to be gasification, where
the resulting gas can either be used as fuel for high efficiency
combusting turbines or as synthesis material for producing liquid
fuels. The U.S. Department of Energy has a series of projects
underway to determine how to most effectively use biomass for energy
production. We’re learning to do that in biomass-coal cofiring
experiments in New York state, and in biogasification experiments
with bagasse (the residue from sugar cane) in Hawaii, with wood in
Vermont, with switchgrass in Iowa, and with alfalfa in Minnesota.
Biomass-based electricity has the important advantage of being a
baseload technology – it can be operated 24 hours a day, unlike
electricity derived from intermitted renewable sources such as solar
and wind. It is also carbon dioxide natural – the carbon dioxide
released during its use is recaptured by the biomass during its
growth. Electricity costs are expected to be competitive as long as
biomass resources costs remain reasonable, and the revenue to be
derived from the sale of biomass resources can be an important
component in rural economic development.
Wind: Many locations in the world offer large wind resources, and wind in the fastest growing energy technology in the world today (from the Dakotas south through the plains states to Texas) have more wind potential than California. Today’s highly reliable machines (typically available 95-98 percent of the time) provide electricity at 5 cents per kilowatt-hour with a 17 mile-per-hour average wind speed. The next generation of turbines, currently under development, should provide electricity at 2.5 cents per kilowatt-hour in 15-mile-per-hour wind regimes and at just under 4 cents per kilowatt-hour in 13 mile-per-hour regimes. Use of wind energy is expending rapidly in many parts of the world, with Europe’s installed capacity now exceeding that of the United States (4000 megawatts versus 1700 megawatts) and India being the third larges market with 800 megawatts. Large wind projects are also being planned for China and other parts of the developing world.
Hydropower is the most mature form of renewable energy, and is already providing a significant share of the world’s electricity. A large potential exists for further hydropower development in many developing parts of the world, but significant expansion in developed countries is unlikely to occur because of environmental concerns.
Wind direction, November, 2002
Questions for text:
Enumerate non-traditional source of energy.
What is biomass and what is it used for?
Give examples of using biomass in the U.S.A.
Where are wind resources used?
What is the most renewable form of energy?