Grammar Study

Participle - see Grammar Database

Word study

Task 5

Match the words with their definitions.

1. electricity

2. electromagnetism

3. electric field

4. magnetic field

5. voltage

6. quantum mechanics

7. quantum electrodynamics

8. conductor

9. insulator

a) the branch of mechanics, based on the quantum theory used for interpreting the behaviour of elementary particles and atoms, which do not obey Newtonian mechanics

b) a material that resists the flow of electric current

c) the movement of free electrons in a material toward an area of positive charges

d) a field of force surrounding a charged particle within which another charged particle experiences a force

e) a fundamental interaction between the magnetic field and the presence and motion of an electric charge

f) a field of force surrounding a permanent magnet or a moving charged particle, in which another permanent magnet or moving charge experiences a force

g) a measure of the propensity of charge to flow from one place to another

h) a relativistic quantum mechanical theory concerned with electromagnetic interactions

i) a material which contains movable electric charges

Reading II (Skimming)

Task 6 I.

Read the text and complete the sentences according to the text.

1. Electromagnetism is responsible for …

2. James Clerk Maxwell was the first to describe…

3. In the 19th century electricity and magnetism …

4. However, electric and magnetic forces …

5. Electric forces are produced by …

6. Magnetic forces are produced by …

7. Electric and magnetic fields are regions …

8. Michael Faraday discovered that …

9. James Clerk Maxwell deduced that …

10. The science of electricity is concerned with …

11. The fundamental concepts of the science of electricity are..

12. A common problem in electricity is …

Electromagnetism is responsible for interactions between charged particles that occur because of their charge, and for the emission and absorption of photons (electromagnetic radiation). The phenomena of electricity and magnetism are consequences of this force, and the relationships between them were first described by James Clerk Maxwell in the 1860s. The physical description of electromagnetism has since been combined with quantum mechanics into the theory of quantum electrodynamics. The electromagnetic force is about 1036 times as strong as the gravitational force.

Electricity and magnetism were long thought to be separate forces. It was not until the 19th century that they were finally treated as interrelated phenomena. In 1905 Albert Einstein’s special theory of relativity established beyond doubt that both are aspects of one common phenomenon. At a practical level, however, electric and magnetic forces behave quite differently and are described by different equations. Electric forces are produced by electric charges either at rest or in motion. Magnetic forces, on the other hand, are produced only by moving charges and act solely on charges in motion.

Electric and magnetic forces can be detected in regions called electric and magnetic fields. These fields can exist in space far from the charge or current that generated them. Remarkably, electric fields can produce magnetic fields and vice versa, independent of any external charge. A changing magnetic field produces an electric field, as the English physicist Michael Faraday discovered in work that forms the basis of electric power generation. Conversely, a changing electric field produces a magnetic field, as the Scottish physicist James Clerk Maxwell deduced.

An important aspect of electromagnetism is the science of electricity, which is concerned with the behaviour of aggregates of charge, including the distribution of charge within matter and the motion of charge from place to place. Different types of materials are classified as either conductors or insulators on the basis of whether charges can move freely through their constituent matter. Electric current is the measure of the flow of charges; the laws governing currents in matter are important in technology, particularly in the production, distribution, and control of energy.

The concept of voltage, like those of charge and current, is fundamental to the science of electricity. Voltage is a measure of the propensity of charge to flow from one place to another; positive charges generally tend to move from a region of high voltage to a region of lower voltage. A common problem in electricity is determining the relationship between voltage and current or charge in a given physical situation.

Reading III

Task 7

Read the text and answer the questions. Make notes while reading and retell the text using questions as a plan:

1) When and where did James Clerk Maxwell live?

2) What was his most significant achievement?

3) Which Maxwell's work was called the "second great unification in physics"?

4) What other discoveries did he make?

5) Maxwell's contribution to the development of science was highly praised, wasn’t it?

James Clerk Maxwell (June 13, 1831 –November 5, 1879) was a Scottish theoretical physicist and mathematician. His most significant achievement was the development of the classical electromagnetic theory, synthesizing all previous unrelated observations, experiments and equations of electricity, magnetism and even optics into a consistent theory. His set of equations—Maxwell's equations—demonstrated that electricity, magnetism and even light are all manifestations of the same phenomenon: the electromagnetic field. From that moment on, all other classical laws or equations of these disciplines became simplified cases of Maxwell's equations. Maxwell's work in electromagnetism was called the "second great unification in physics", after the first one carried out by Isaac Newton.

Maxwell demonstrated that electric and magnetic fields travel through space in the form of waves, and at the constant speed of light. Finally, in 1864 Maxwell wrote "A dynamical theory of the electromagnetic field", where he first proposed that light was in fact undulations in the same medium that is the cause of electric and magnetic phenomena.

Maxwell also developed the Maxwell distribution, a statistical means to describe aspects of the kinetic theory of gases. These two discoveries helped usher in the era of modern physics, laying the foundation for future work in such fields as special relativity and quantum mechanics.

Maxwell is also known for creating the first true colour photograph in 1861.

Maxwell is considered by many physicists to be the nineteenth century scientist with the greatest influence on twentieth century physics. His contributions to the science are considered by many to be of the same magnitude as those of Isaac Newton and Albert Einstein. On the centennial of Maxwell's birthday, Einstein himself described Maxwell's work as the "most profound and the most fruitful that physics has experienced since the time of Newton." Einstein kept a photograph of Maxwell on his study wall, alongside pictures of Michael Faraday and Newton.

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