TASK 4. Choose the correct answer according to the text.
According to the text, what is the best element for transistor production?
oxygen
silicon
copper
According to the text, polythene is resistant to electricity and it is used for
insulating.
making electric cable.
regulating the current flow.
Which of these materials is not the material of very low resistance?
germanium
copper
iron
Which of these characteristics is not common for silicon?
It is solid.
If has the ability to conduct electricity.
If is often used as an insulator.
“dopants” are
elements, which are resistant to electricity.
impurities, to which silicon is very sensitive.
the most common elements on the Earth.
TASK 5. Find the words opposite in meaning.
Solid, bottom, right, liquid, insulator, top, increase, positive, drop, high, left, little, conductor, negative, much, low.
TASK 6. Translate the words, pay attention to the suffixes.
resist, resistance, resistant
insulate, insulation, insulator, insulated, insulating
conduct, conductor, conductivity, conductance, conduction, conductive
electricity, electric, electrician, electrify, electrical
TASK 7. Change the sentences from active into passive.
Nowadays people use silicon to produce transistors. Nowadays silicon…
Usually we insulate copper wire with polythene. Usually copper wire…
We use iron and copper for making electric cable. Electric cable…
You can increase conductivity of silicon by adding a dopant to it. Conductivity of silicon…
You can form a p-n junction by doping a silicon crystal with p and n type dopants. P-n junction…
Professor applied a voltage to one of the contacts to show us the work of the p-n junction. A voltage…
TASK 8. Fill in the gaps with the following prepositions: to, with, of, on, in, through, at, into
A semiconductor chip is a tiny board made … silicon and germanium. 2. All elements can be divided … three groups; the first group includes the elements resistant ... electricity; the second one includes the elements … low resistance; and the last one includes semiconductors. 3. He said that it would be better to insulate this piece of copper wire … polythene. 4. If we look … the scheme of a p-n-p junction we can see that … the right there is an emitter, … the left there is a collector and … the middle you can see a base. 5. Compass is a device which is very sensitive … the magnetic field of the earth. 6. Each layer of semiconducting material is doped … a small amount of impurity. 7. You should connect each of the two parts of the system … separate sources of power. 8. This method can be applied … the production of new electronic devices. 9. Let’s look at the Mendeleyev Periodic Table of elements. Such elements as hydrogen, oxygen, carbon and nitrogen are placed … the top of table and such elements as lead, gold, mercury are … the bottom of it. 10. They say that current flows … a vacuum in only one direction.
TASK 9. Match the words with their meanings.
junction
electricity
transistor
silicon
oxygen
conduct
raw material
voltage
insulate
resist
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1. electronic device, much smaller than a radio valve, used in radio sets, usually made of silicon.
2. one of the most common elements, semiconductor, used in different electronic devices.
3. chemical element, gas without color, taste or smell, present in air, necessary to the existence of all forms of life.
4. in the natural state, not manufactured for use.
5. be unaffected by something.
6. cover or separate something with non-conducting materials to prevent passage of electricity.
7. property of conduction, developed in and around substances by rubbing to produce light.
8. transmit, allow to pass along or through.
9. electrical force measured in volts.
10. joining or being joined.
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