ответить на вопросы 2, 6 (на 2 вопрос дать определение на английском с текста) I. Read the text
THE NATURE OF ELECTRICITY
Practical electricity is produced by small atomic particles known as elec-
trons. It is the movement of these particles which produce the effects of heat
and light.
The pressure that forces these atomic particles to move, the effects they
encounter opposition and how these forces are controlled are some of the prin-
ciples of electricity.
Accepted atomic theory states that all matter is electrical in structure. Any
object is largely composed of a combination of positive and negative particles
of electricity. Electric current will pass through a wire, a body, or along a
stream of water. It can be established in some substances more readily than in
others, that all matter is composed of electric particles despite some basic dif-
ferences in materials. The science of electricity then must begin with a study of
the structure of matter.
Matter is defined as any substance which has mass (or weight) and occupies
space. This definition should be broad enough to cover all physical objects in the
universe. Wood, water, iron, and paper are some examples of matter. Energy is
closely related to, but not to be confused with, matter. Energy does not have
mass, and it does not occupy space. Heat and light are examples of energy.
The smallest particle of matter which can be recognized as an original
substance was thought to be a unit called the atom. Recently scientists have
found particles even smaller than atoms, but our theories are still based on the
atom. The atom consists of a nucleus and a cloud of electrons. It is generally
agreed that the electrons are small particles of electricity, which are negative in
nature. These particles orbit the nucleus in much the same fashion that planets
orbit a sun.
II. Guess the meaning of the following international words:
Electricity, electron, effect, structure, combination, material, mass, energy,
atom, orbit
VI. Answer the questions:
1) What are the principles of electricity? 2) What must the science of
electricity begin with? 3) Are there any differences between energy and mat-
ter? What are they? 4) What is recognized as an original substance now?
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The scientist (had been preparing) the article for two hours before midnight.
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