Unit 3
Grammar:
Present Participle
Continuous Tenses (Active, Passive)
Quantifiers: some, any, no, much, many, little, a little, few, a few
Reading Exercises
Practice reading the following one-syllable words:
few, force, work, push, pull, change, rest, case, weight, lie, ground, stone, done, sense, word, hold, true, through, mean, kind, fall, store, flow, use, wheel, coal, thrown, heat, burn.
Practice reading the following two-syllable words with the stress on the first syllable:
equal, product, body, order, over, meaning, language, distance, turbine, differ, factor.
Practice reading the following two-syllable words with the stress on the second syllable:
among, connect, apply, perform, effect, possess, begin, refer, demand, belong, result, produce, account, amount, divide, require.
Practice reading many-syllable words:
Chemical, definite, different, determine, multiply, operate, ability, energy, mechanical, physical, calculate, multiply, electrical, everyday, scientific.
Practice reading the following word-combinations:
Taken into account, for example, in order to, in fact, in the language of science, in everyday life, connected with the idea of time, a state of rest, a state of motion, from motion to rest, in scientific sense of the word, the force is applied, to result in no work, the amount of performed work, the product of the force by the distance, the ability to work, different kinds of energy, all moving bodies, to drive the waterwheels of turbines.
Text 3 a force, work, energy and power
In the language of science a few words, among them force, work, energy and power, have definite meanings differing a little from the meanings that are often given to them in everyday life.
The word “force” meaning a simple push or pull, is not connected with idea of time. When forces are pushing upon an object or pulling upon it, they change it from a state of rest to a state of motion or from motion to rest.
Work is done when a force is acting over a distance. In this case, too, the time is not taken into account. For example, work is done when a weight lying on the ground is lifted, when a stone is thrown. However, no work is done in the scientific sense of the word when a man is standing and holding a weight. True, the force is applied, but it results in no work.
The amount of performed work is determined by two factors: the applied force and the distance through which the force acts. In order to calculate the amount of work, the force is multiplied by the distance, that is, the amount of performed work is equal to the product of the force by the distance
Work
= Force
Distance or W = F
S
When we are speaking of power, time is taken into account. Power means the rate at which work is done. It is equal to the work divided by the time which is required to perform it.
Power
= Work/Time = (F
S)/t
The ability to do work is called energy. There are different kinds of energy: mechanical, chemical, electrical, heat and light energy. All moving bodies, in fact, possess it. For example falling water has a store of energy, for as it is flowing down it can be used to drive the water-wheels of turbines. Coal and other fuels also hold a store of energy. It can be made use of when we are burning fuels to produce steam.
Notes:
a state of rest – стан спокою
a state of motion – стан руху
to take into account – приймати до уваги