Exercise 2. Read and translate the text

Принести данный материал на урок.

Выполнить письменно упражнение 1 из Unit1.

(знать правильное произношение слов и их перевод)

Unit 1. Energy. Types of Energy

Exercise 1. Read and translate the following words and word-combinations

1) universe

2) to define precisely

3) a scalar quantity

4) to denote the amount of work

5) total amount of energy

6) the law of conservation of energy

7) cannot be created or destroyed

8) to encounter

9) to possess

10) motion

11) the process of respiration

12) inter-atomic bonds in molecules

13) the vibrational, rotational and translational motion

14) elastic energy

15) to be derived from

16) equation

17) nuclear fission

18) the result of compression and rarefaction

19) from the oscillatory motion

20) renewable energy

Exercise 2. Read and translate the text

Every single thing in the universe is an expression of energy and every action is an energy transformation. Energy keeps changing forms and that is what makes it difficult to define precisely.

What is Energy? In Physics, energy is defined as a scalar quantity which denotes the amount of work that can be done by a force under certain constraints. Energy transforms from one into many forms, but if you make a sum of all this amount of energy transformed in different forms, the sum total remains constant. This is the law of conservation of energy. The universe as a whole is a closed system and therefore, the total amount of energy in the universe remains constant. In every isolated system, since the total energy remains constant, energy can only change form. Energy cannot be created or destroyed; it can only be changed from one form to another.
Every kind of change that happens in the universe is an energy transformation. Energy may be classified in a variety of ways. It could be classified according to the different energy sources or according to the force that causes the energy change. Let us get acquainted with the different forms of energy that we encounter in our day-to-day life:
Potential Energy & Kinetic Energy: Potential energy is the energy a particle or an object possesses on account of its position in a conservative force field, while kinetic energy is the energy which a particle possesses due to its motion. All forms of energy can basically be classified into potential energy, kinetic energy or a mixture of both.

Gravitational Energy. Gravitational energy is the energy possessed by an object according to its position in the gravitational field.

Chemical Energy. The motive force that powers the human body, is provided by the chemical energy derived through the process of respiration. Chemical energy is derived from the making and breaking of inter-atomic bonds in molecules. Through molecular rearrangements, the biological world derives energy. The energy derived from gasoline is an example of chemical energy utilization.
Thermal Energy. Thermal or heat energy is the sum total of kinetic and potential energy of atoms and molecules that form a substance. Thermal energy can be measured by the temperature of the system under consideration. It is the energy of a substance, due to the vibrational, rotational and translational motion and potential energy of atoms and molecules.
Electric Energy. This is the energy derived from the electrical potential energy that exists between charges, which is delivered in the form of an electric current. When you connect the terminals of a battery with a bulb, electrical energy flows between the two terminals, in the form of the electric current, which are actually electrons traveling through the wire.
Elastic Energy. When you stretch a rubber band and then release it, the interatomic forces make it snap back to its original condition. The stored elastic potential energy is converted into kinetic energy to create the reversible motion which brings the elastic band to its original position.

Nuclear Energy. The energy derived from the conversion of a fractional nuclear mass into energy is nuclear energy. Defined by the celebrated Einsteinian equation - 'E=mc2' (where E is energy, m is lost mass and c is the speed of light), this energy is derived by inducing nuclear fission in certain radioactive isotopes like Uranium.

Sound Energy. Every sound that you hear, is the result of compression and rarefaction waves produced in air as a medium. Thus sound energy is derived from the oscillatory motion of air molecules.

Wind Energy. Wind energy is the mechanical energy derived from wind motion.

Solar Energy. It is the heat radiated by the Sun in the form of electromagnetic waves, which can be converted into electrical energy through solar cells. The solar energy drives the whole ecosystem on Earth. It is a type of renewable energy.

All the energy transformations in the world, outside the atomic nucleus are governed by two forces which are the electromagnetic force and the gravitational force. So, all the forms of energy like thermal energy, chemical energy are forms of electromagnetic energy. The rest of the forms are a combination of electromagnetic and gravitational energy transformations.

Exercise 3. Find English equivalents to the following words and word-combinations.

Количество, качество, преобразование энергии, закон сохранения энергии, точно, вселенная, постоянный, создавать, разрушать, источники энергии, сталкиваться в повседневной жизни, кинетическая, потенциальная, движущая сила, тепловая, электрическая, клеммы батареи, электрический ток, химическая, расщепление ядра, возобновляемые источники энергии, обладать.

Exercise 4. Fill in appropriate words

1.This is the law of … of energy.

2.In every … system energy can only change form.

3.Energy cannot be … or …; it can only be changed from one … to another.
4.Energy may be classified according to the force that causes the...

5. … energy is the energy a particle or an object possesses on account of its position in a conservative force field.

6. … energy is the energy which a particle possesses due to its motion.

7. … energy is the energy possessed by an object according to its position in the gravitational field.

8. … energy is derived from the making and breaking of inter-atomic …in molecules.

(destroyed, energy change, bonds, potential, conservation, form, kinetic, gravitational, created, chemical, isolated)

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