I. Find out the words in the dictionary. Write them down and learn

IV. Practice the following speech patterns.

Pattern 1. Jelly is neither a true solid nor a liquid.

1. smoke – a pure gas, a solid

2. liquid crystal – a solid, a gas

3. plasma – a solid, a gas

Pattern 2. The difference depends upon the particle size.

1. pattern

2. structure

3. temperature

4. dispersion medium

5. disperse phase

6. molecule size

Pattern 3. The pattern can be altered by heat.

1. temperature

2. external forces

3. internal forces

4. electric field

5. electrical voltage

6. magnetic field

V. Find the sentences that can’t be found in the text.

1. Some substances exist in states that do not comply with the normal definitions of a gas, a liquid or a solid.

2. Colloids are classified according to the physical state of the dispersion medium and the disperse phase.

3. Colloids have different properties from those of true solutions because of the size of the particles.

4. Colloidal particles nearly always carry an electrical charge.

5. Some liquid crystals change colour at certain temperatures.

6. A plasma is created by heating a gas to such a high temperature that its atoms or molecules lose electrons and become ions.

VII. Translate the following word combinations and noun groups into Uzbek.

1. not to comply with the normal definition of a gas _____________

2. true solid ___________________________________________

3. neither a solid nor a liquid _______________________________

4. to exist as a plasma ____________________________________

5. in general __________________________________________

6. temperatures approaching absolute zero ____________________

7. to diffuse through parchment ____________________________

8. he was broadly correct __________________________________

9. atoms and molecules are arranged in a pattern ________________

10. liquid crystal thermometers _____________________________

11. to cause a change _____________________________________

12. liquid crystal displays ________________________________

VIII. Fill in the missing words.

1. Some substances exist in states that do not _____ with the normal definitions of a gas, a liquid or a solid.

2. Smoke is neither a _____ gas nor a solid.

3. Matter in stars and in the tails of comets exists as a plasma, a _____ of charged particles.

4. Although they are strictly not different states of matter, their _____ is exceptional.

5. In 1861, the physical chemist Thomas Graham discovered that some substances in _____, such as salt and sugar, _____ through parchment.

6. He believed that the difference between a crystalloid and a colloid depended largely upon _____ _____.

7. A colloid is _____ in which the component particles are large molecules or clumps of small molecules.

8. The liquid state is _____ between the solid state and the gaseous state.

9. In a liquid crystal the atoms or molecules are _____ in a pattern, like those of a solid crystal.

10. The pattern is not completely fixed; it can be _____ by heat or an electric field.

11. In some liquid crystals an electrical _____ causes a change in pattern that alters the plane of polarized light.

12. The gas is almost fully ionized and becomes a very good electrical _____.

IX. Fill in the prepositions if necessary.

1. Some substances exist ___ states that do not comply ___ the normal definition ___ a gas, liquid or a solid.

2. ___ general, plasma can exist only ___ extremely high temperatures.

3. ___ extremely low temperatures, approaching ___ absolute zero, some materials take ___ remarkable properties.

4. ___ 1861 Thomas Graham discovered that some substance ___ solution diffuse ___ parchment.

5. He believed that the difference ___ a crystalloid and a colloid depended largely ___ particle size.

6. ___ a liquid crystal the atoms or molecules are arranged ___ a pattern.

7. The pattern can be altered ___ heat or an electric field.

8. A plasma is described as being the fourth state ___ matter; that is, one phase farther ___ ___a gas.

9. ___ fact, a plasma is created ___ heating a gas ___ such a high temperature that its atoms or molecules lose electrons and become ions.

10. Scientists are trying to recreate such a plasma ___ earth now.

X. Define whether the sentences are true or false.

1. Matter in stars and in the tails of comets exists as a gas.

2. A plasma can exist only at extremely low temperatures.

3. At extremely low temperatures approaching absolute zero some

materials take on remarkable properties.

4. Thomas Graham divided substances into two groups: «true» and

amorphous.

5. In a liquid crystal the atoms or molecules are not arranged in a pattern.

6. Some liquid crystals change colour at certain temperatures.

7. A plasma is sometimes described as being the fifth state of matter.

8. The gases that are involved in the thermonuclear reactions of the

sun and other stars are in the form of a plasma.

XI. Practice with someone asking and answering.

1. Are there states of matter that do not comply with the normal

definitions of a gas, a liquid or a solid?

2. What are the examples of unusual states of matter?

3. Are they strictly different states of matter?

4. When did the physical chemist Thomas Graham make experi-

ments with substances in solution?

5. What did he discover?

6. How did he call substances that would diffuse through parchment?

7. What substances were called colloids?

8. What is the definition of a colloid?

9. Are there any substances that are intermediate between solids

and liquids?

10. What happens in a liquid crystal?

11. What is a plasma?

12. In what way is a plasma created?

XII. Put questions to the following sentences.

1. A plasma can exist only at extremely high temperature. (Alternative)

2. In 1861 Thomas Graham discovered crystalloids and colloids.

(Special)

3. Some liquid crystals change colour at certain temperature. (Gen-

eral, disjunctive)

XIII. Dictate the following sentences in English to your fellow-students. Check them together.

1. Some substances exist in states that do not comply with the normal definitions of a gas, a liquid or a solid.

2. In 1861 the physical chemist Thomas Graham discovered that some substances in solution diffuse through parchment.

3. He believed that the difference between a crystalloid and a colloid depended upon particle size.

4. In a liquid crystal the atoms or molecules are arranged in a pattern.

5. A plasma is created by heating a gas to a high temperature.

UNIT 7

I. Find out the words in the dictionary. Write them down and learn.

behaviour, intrinsic, to depend on, to define, gravity, to attract,

friction, viscous force, resistance, downward force, upward force,

strength, density, per unit volume, specific gravity, to be equal, to

prevent, to be equal

II. Read the text. Use a dictionary, if necessary.

TEXT: «STATICS»

Statics is the branch of physics that deals with the behavior of bodies that are held stationary under the influence of a system of forces. The study of statics depends crucially on an understanding of the concept of force, which can be defined as an agent that is capable of altering the state of rest or motion of an object. The most common force is that of gravity which on earth attracts everything downwards to its surface. Other forces include friction, which in some cases can act against another force to prevent movement, and the viscous force that acts against the force of gravity when a small object is dropped into, for example, a container of syrup. The action of a force depends on the mass of the object on which it is exerted. Mass is defined as the resistance of an object to any change of its state of motion or rest by the action of a force. Mass is, therefore, a measure of the inertia of an object. The greater an object’s mass, the smaller is the acceleration, that a given force produces. The weight of an object is not, however, an unchanging intrinsic property. It is the downward force of an object resulting from the action of the force of gravity. So, although an object’s mass is the same everywhere, its weight depends on the strength of the gravitational field acting on it. One of the major areas of study in statics is the behavior of objects in fluids (that is, in liquids and gases). Much of this work revolves around the concept of density, which is the mass of an object per unit volume. Another useful concept is that of specific gravity, or relative density. This property is given by the density of an object divided by the density of water. An important law in the statics of fluids is Archimedes’ principle. It states that the upward force acting on an object immersed in a fluid is equal to the weight of fluid that is displaced. The value of the principle lies in providing a way of finding the specific gravity, and therefore the density of an object without measuring both its mass and volume. Legend tells of Archimedes applying the principle after being asked by the King of Syracuse to prove that a gold crown was indeed made of solid gold. The crown was intricately worked and finding its volume would have been extremely difficult. So Archimedes found its density by putting the crown and then an equal weight of pure gold in a bowl of water and measuring the amount of water displaced by each. He found that the crown displaced more water than the gold weight did. It meant that the crown had a greater volume and therefore consisted of a material of lower density than pure gold.

III. Form nouns from the following verbs by adding the suffixes

-er, -or, -tion, -sion, -ty, -ance, etc. or not changing anything. Translatethe nouns.

To depend on, to influence, to force, to understand, to define, to

move, to attract, to act, to prevent, to resist, to change, to accelerate, to

produce, to revolve, to divide, to displace, to measure, to provide.

IV. Practice the following speech patterns.

Pattern 1. Statics deals with studying the behaviour of

stationary bodies.

physics – the properties of bodies

theoretical physics – the laws and principles

experimental physics – the experiments and observation

statics – the behaviour of stationary bodies

dynamics – the behaviour of bodies under the influence of forces

Pattern 2. The study of statics depends on the concept of force.

the development of other sciences – the knowledge of physical phenomena

the action of a force – the mass of the object

an object’s weight – the strength of the gravitational field

Pattern 3. Mass is defined as the resistance of an object to any change.

force – an agent that can alter the state of rest or motion of an object

ravity – a force that on earth attracts everything downwards to its surface friction – a force that can act against another force to present movement

V. Find the sentences that can’t be found in the text.

1. The study of statics depends crucially on an understanding of the concept of force.

2. The most common force is that of gravity, which on earth attracts everything downwards to its surface.

3. The moon’s gravitational fields, for example, is only one-sixth as powerful as the earth’s, and as a result the weight of an object on the moon is only one-sixth of its weight on earth.

4. One of the major areas of study in statics is the behaviour of objects in fluids.

5. If the mass is measured in kilograms and the unit of volume is the cubic meters, then density is measured in kilograms per cubic meter.

6. An important law in the statics of fluids is Archimedes’ principle.

7. The density of liquids is measured by hydrometers.

VII. Find Uzbek equivalents to the following expressions in the text.

1. branch of physics ____________________________________

2. the concept of force ___________________________________

3. bodies that are held stationary ___________________________

4. can be defined as _____________________________________

5. the most common force is that of gravity ____________________

6. attracts everything downwards to its surface _________________

7. a measure of inertia ___________________________________

8. an unchanging intrinsic property __________________________

9. revolves around the concept of density _____________________

10. Archimedes’ principle states ___________________________

11. an object immersed in a fluid ____________________________

12. is equal to _________________________________________

13. the value of the principle lies ___________________________

14. to measure both its mass and volume ______________________

15. amount of water ____________________________________

VIII. Fill in the missing words.

1. Statics is the branch of physics that ______ with the ________

of bodies.

2. The study of statics _________ crucially on an understanding of

the concept of force.

3. Other forces include _______, which in some cases can act against

another force to prevent movement.

4. Mass is _________ as the _________ of an object to any change

of its state of motion or rest.

5. Mass is, therefore, a __________ of the ________ of an object.

6. The weight of an object depends on the _________ of the grav-

itational field acting on it.

7. _______ _______ is given by the density of an object divided by

the density of water.

IX. Fill in the prepositions if necessary.

1. Statics is the branch ____ physics that deals ____ the behaviour ____

bodies that are held stationary ____ the influence of a system ____ forces.

2. Other forces include friction which ____ some cases can act ____

another force to prevent movement.

3. The action ____ a force depends ____ the mass ____ an object.

4. Mass is a measure ____ the inertia ____ an object.

5. It is the downward force of an object resulting ____ the action ____

the force ____ gravity.

6. Much ____ this work revolves ____ the concept ____ density.

7. Density is the mass ____ an object ____ unit volume.

8. The property is given ____ the density ____ an object divided ____

the density ____ water.

9. Archimedes found its density ____ putting the crown ____ a

bowl ____ water.

10. The weight ____ an object is equal ____ the weight ____ fluid

displaced.

X. Define whether the sentences are true or false.

1. Statics is the branch of physics.

2. The study of statics depends crucially on an understanding of

the concept of quantum.

3. The most common force is that of gravity which on earth attracts

everything downwards to its surface.

4. Mass is defined as the attraction of objects to each other.

5. Mass is, therefore, a measure of the energy of an object.

6. The weight of an object is an unchanging intrinsic property.

7. One of the major areas of study in statics is the behaviour of

objects in fluids.

XI. Practice with someone asking and answering.

1. What is statics?

2. What does the study of statics depend on?

3. Give the definition of the force.

4. What are the examples of different forces?

5. What does the action of a force depend on?

6. In what way is mass defined?

7. Is the weight of a body an unchanging intrinsic property?

8. It is the downward force of an object resulting from the action of

the force of gravity, isn’t it?

9. What is one of the major areas of study in statics?

10. What concept does much of this work revolve around ?

11. What do you know about specific gravity or relative density?

12. What does Archimedes’ principle state?

XII. Put questions to the following statements.

1. Statics deals with the behaviour of bodies.

2. Mass is a measure of the inertia of an object.

3. Archimedes found the density of the gold crown.

XIII. Dictate the following statements in English to your fellow-students.

1. Statics is the branch of physics that deals with the behaviour of bodies.

2. The most common force is that of gravity which on earth attracts everything downwards to its surface.

3. Other forces include friction and viscous force.

4. Density is the mass of an object per unit volume.

UNIT 8

I. Find out the words in the dictionary. Write them down and learn.

kinematics, dynamics, gravitational force, to offset, linear mo-

tion, circular motion, simple harmonic motion, to oscillate, displace-

ment of a particle, origin, velocity, speed, momentum, the law of

universal gravitation, to move uniformly, per hour

II. Read the text. Use a dictionary, if necessary.

TEXT: «DYNAMICS. LAWS OF MOTION»

Dynamics is the study of the ways in which objects behave when they are acted on by forces. Such forces are all around us – for example, the gravitational force acting on a falling object, the air resistance that offsets the full effect of gravity on it, and the frictional force that makes it difficult to drag an object along the ground. Just as there are many different types of forces, there are also different types of motion produced by those forces. In linear motion, an object moves in a straight line and a falling body is an example. Circular motion is produced when an object is acted on by a force that originates from a central point. If an object is held in equilibrium by two forces, and the extra force resulting from slightly moving the object from its equilibrium position is directly proportional to the distance moved, then the object oscillates regularly in simple harmonic motion. For an understanding of dynamics, it is necessary to have a knowledge of kinematics, which is the study of motion alone, without taking into account what causes the motion. The most basic concept in kinematics is that of the displacement of a particle; this is the length and direction of the line along which the particle moves from some fixed point, the origin. A quantity, in which both magnitude and direction are specified, is called a vector. And vectors are of great importance in physics. The next concept is that of the velocity of the particle. It is defined as the rate of change of the displacement with time. Velocity is itself a vector. The commonly-used word speed is reserved by physicists to denote only the magnitude of an object’s velocity, but not its direction. Any quantity that measures only the magnitude of some phenomenon and not its direction as well is known as a scalar quantity. Multiplying the velocity of an object by its mass gives us another vector quantity – momentum. When the velocity of an object changes, it either accelerates or decelerates. The rate of change of velocity with time is measured in meters per second per second (ms -2 ) or an equivalent unit such as kilometers per hour per hour (km hr -2 ). Acceleration itself can vary with time. The fundamental problem of dynamics is determining the motion of an object acted on by forces. The three basic laws governing this behaviour are called Newton’s laws of motion, after the English mathematician and physicist Isaac Newton (1642-1727), who formulated them in the seventeenth century, along with the law of universal gravitation. Newton’s first law of motion states that an object will remain at rest or will continue to move uniformly in a straight line at constant velocity unless acted on by a force. Newton’s second law goes a stage further to describe how an object behaves when a force does act on it. This law states that the rate of change of momentum of an object is proportional to the force acting on it. Newton’s third law of motion concerns the interaction of forces produced by objects. It states that if one object exerts a force on another, that second object exerts an equal and opposite force on the first. This is the principle of action and reaction. A common example of this principle in operation occurs when someone tries to step onto land from a boat. In getting out of the boat, the person exerts a force on it. So as he goes forward onto land, the boat is pushed in the other direction.

III. Form adverbs from adjectives by adding the suffix - ly and translate them.

Different, straight, central, slight, direct, proportional, regular, sim-

ple, harmonic, basic, great, common, fundamental, universal, uniform,

constant, necessary, original.

IV. Practice the following speech pattern.

Pattern 1. For an understanding of dynamics, it is necessary

to have a knowledge of kinematics.

1. dynamics – statics

2. physics – nature of matter

3. motion – forces

4. kinematics – the displacement of a particle

5. kinematics – vectors and scalars

6. kinematics – momentum

7. momentum – velocity

8. gravity – dynamics

9. acceleration – kinematics

V. Find the sentences that can’t be found in the text.

1. Just as there are many different types of forces, there are also

different types of motion produced by those forces.

2. The most basic concept in kinematics is that of the displacement of a particle.

3. The three basic laws governing this behaviour are called Newton’s laws of motion.

4. Using Newton’s laws it is possible to find the position of a body by a knowledge of the relation between that position and its velocity or rate of change of velocity at any other time.

5. The calculus, developed by Newton, could be used and was

used by him for solving a great variety of mechanical and hydrodynamic problems.

6. The object of Newton was to demonstrate how universal gravity could maintain the system of the world.

7. Newton established, once and for all, the dynamic view of the universe instead of the static one and showed that the universe was regulated by simple mathematical laws.

VI. Put the following sentences in the right order.

1. When the velocity of an object changes, it either accelerates or decelerates.

2. For an understanding of dynamics, it is necessary to have a knowledge of kinematics, which is the study of motion alone.

3. Dynamics is the study of the ways in which objects behave when they are acted on by forces.

4. The fundamental problem of dynamics is determining the motion of an object acted on by forces.

5. Just as there are many different types of forces, there are also different types of motion produced by those forces: linear motion, circular motion, simple harmonic motion.

6. The next concept is that of the velocity of the particle.

7. The most basic concept in kinematics is that of the displacement of a particle.

VIII. Find Uzbek equivalents to the following expressions in the text.

1. the ways in which objects behave _________________________

2. the gravitational force _________________________________

3. air resistance ________________________________________

4. frictional force _______________________________________

5. linear motion ________________________________________

6. circular motion _______________________________________

7. a force that originates from a central point ___________________

8. the extra force resulting from ___________________________

9. equilibrium position __________________________________

10. the distance moved __________________________________

11. causes the motion ____________________________________

12. the displacement of a particle ___________________________

13. quantity ___________________________________________

14. magnitude __________________________________________

15. momentum ________________________________________

16. can vary with time ____________________________________

17. the law of universal gravitation __________________________

18. to move uniformly in a straight line _______________________

19. exerts a force on another object __________________________