K. Put down the title corresponding to each of the given descriptions.

1. Titles: electric current; direct current; alternating current; continuous current.

__________ A current which always flows in one and the same direction

__________ A flow of passage of electricity along an electric circuit, usually measured

in amperes

__________ A current which periodically alternates or reverses in direction.

__________ A current uniform both in strength and in direction, a steady direct current.

2. Titles: energy; electric energy; chemical energy; radiant energy; kinetic energy;

potential energy.

___________ The capacity of doing work.

___________ That part of the energy stored within an atom or molecule which can be

released by a chemical reaction.

___________ The energy which a body possesses by virtue of its position. It is measured by

the amount of work the body performs in passing from that position to a

standard position in which the energy is considered to be zero.

___________ The energy which a body possesses by virtue of its motion.

__________ The energy associated with electric charges and their movements. It is measu-

red in watt seconds ( joules) or kilowatt-hours.

3. Titles: electric field; direct current; alternating current; electromagnetic radiation;

continuous wave; electromagnetic spectrum.

___________ Radiation consisting of waves of energy associated with electric and

magnetic fields. This radiation is emitted by matter in units called photons.

___________ The range of frequencies over which electromagnetic radiations are

propagated. The lowest frequencies are radio waves, increases of frequency

produce infrared radiation, light, ultra-violet radiation, X-rays, gamma rays

and finally the radiation associated with cosmic rays. Radio or radar

transmissions which are generated continuously and not in short pulses.

___________ An electric current flowing always in the same direction.

___________ A flow of electricity which, after reaching a maximum in one direction,

decreases, finally reaching a maximum in the opposite direction, the cycle

being repeated continuously. The number of such cycles per second is the

frequency.

___________ The region near an electric charge, in which a force is acting on a charged

particles.

4. Titles: two-phase system; single-phase system; three-phase system; poly-phase system.

_____________ An AC. distributing system employing a single phase at A.C. supplied by the

generator.

_____________ An A.C. distributing system utilizing a number of alternating currents

differing in phase.

_____________ An A.C. system employing three alternating currents of equal strength,

differing in phase by one-third of a cycle.

_____________ An A.C. system employing two alternating currents of equal strength,

differing in phase by a quarter cycle, or such that one current has maximum

strength when the other is passing through zero.

L. Arrange the following words in the pairs of synonyms.

a) 1. amount; 2. big; 3. matter; 4. application; 5. at present; 6.research; 7.to step down;

8. tube; 9.appliance; 10.minute; 11.arrow.

b) 1. investigation; 2.device; 3. needle; 4. quantity; 5. substance; 6.to lower; 7. small;

8. large; 9. new; 10. use;11. pipe.

M. Find nouns from the following words using suitable suffixes.

construct, develop, consider, distribute, deflect, equip, connect, require, produce, state, suit.

Date: 2014-12-28; view: 2254