Answer the questions:

1. When do forces change an object form a state of rest to a state of motion?

2. When is work done?

3. Is a man performing work when he is standing and holding a weight?

4. What is the amount of performed work determined by?

5. How is the amount of performed work calculated?

6. What is power?

7. What is power equal to?

8. What is energy?

9. Are there different kinds of energy?

10. What are they?

Exercises:

1. Translate the following words paying attention to the suffixes:

1. operate – operation – operator – operable – operative

2. act – action- active- activity

3. mechanics – mechanic – mechanical – mechanism – mechanization

4. electricity – electric – electrification – electrify – electrician

5. industry – industrial – industrialization – industrialist – industrious

6. science – scientist – scientific – scientifically

2. Translate the adjectives paying attention to the negative prefixes:

incorrect, unkind, dissimilar, immovable, irresistible, disloyal, uncomfortable, incomparable, illogical.

3. Give verbs of the same root and translate them:

assistance, education, establishment, expression, existence, receiver, equipment, exhibition, reference.

4. Translate the following word-combinations:

a few words, the language of science, to connect with, to change an object from a state of rest to a state of motion, to act over a distance, in this case, to take into account, to lift a weight, to throw a stone, the scientific sense of the word, to result in, the amount of, the applied force, in order to, to multiply by, to be equal to, to divide by, kinds of energy.

1. Translate the sentences paying attention to different meanings of the words in bold type:

1. Many electric stations use the power of water.

2. One horse power equals 75 kilogram –meters.

3. This power station was built 10 years ago.

4. Scientists achieved good “results” in constructing semiconductor devices.

5. The application of this device results in better operation of the equipment.

6. These forces “change” the direction of motion.

7. The “change” of the state of matter was caused by heat.

6. Fill in the blanks with the words given below:

1. Bodies that are not in … often have great capacities for doing work.

(1. power 2. weight 3. motion)

2. In physics the term “work” is defined as a … of force and motion in the direction of force.

(1. sum 2. product 3. division)

3. Pushing something along the floor against friction … doing work.

(1. means 2. defines 3. connects)

4. Bodies in the … of rest often have great capacities for doing work.

(1. sense 2. state 3. force)

5. The kinetic energy of a body is the energy which it … because of its speed.

(1. throws 2. possesses 3. applies)

6. Work and energy are closely …

(1. acted 2. observed 3. connected)

7. The internal energy of a body is … by work and also by heat transfer without work.

(1. used 2. changed 3.travelled)

8. Energy is the law … all natural phenomena.

(1. leading 2. possessing 3. governing)

1. Arrange the following words in pairs of synonyms and translate them:

1. application a) vapour

2. steam b) for instance

3. possess c) force

4. in fact d) use

5. for example e) keep

6. require f) do

7. hold g) really

8. perform h) have

9. power i) way

10. means d) demand

11. often k) motion

12. rest e) seldom

8. Translate the following international words:

distance, lift, act, calculation, mechanics, mechanical, chemistry, chemical, electricity, electrical, energy, turbine, product , produce, operate, operator, idea, object, special.

9. Make up pairs of the following words and translate them:

1) burning a) force

b) energy

c) fuel

2) driving a) weight

b) rest

c) wheel

3) growing a) nature

b) weight

c) example

4) working a) word

b) machine

c) productions

5) changing a) force

b) fact

c) equality

6) mechanical a) meaning

b) energy

c) ground

7) falling a) distance

b) water

c) state

1. Fill in the blanks with the prepositions given below: to, of, at, in, on, with, for, from, by:

1. Great amounts … energy are sent … us … the sun.

2. Part … this energy comes … the sun … the form … light.

3. The energy … light differs … other kinds … energy.

4. Light energy is stored … such fuels as coal, … example.

5. Steam … a steam engine is produced … a boiler.

6. When a weight is lifted … the ground, a definite amount … work is done.

7. A change … a state … rest … a state … motion is connected … the application … force.

8. Physics is taught … all technical colleges.

9. When a weight is lying … the ground, no work is done.