Проверьте, знаете ли Вы следующие слова и словосочетания, необходимые для понимания текста.

a) Найдите в правой колонке русские эквиваленты:

    1. to process                              1. увеличение

    2. to enhance                                   2. видеть, рассматривать

    3. magnification                        3. экран

    4. to view                               4. обрабатывать

    5. screen                                     5. увеличивать, усиливать

б) Найдите в правой колонке английские эквиваленты:

    1. удлинение, протяжение     1. to relate

    2. преобразовывать                           2. extension

    3. сетчатка (глаза)                 3. to intersect

    4. быть связанным, относиться 4. to transform

    5. перекрывать, пересекаться 5. retina

OPTICAL INSTRUMENTS

An optical instruments either processes light waves to enhance an image for viewing, or analyzes light waves (or photons) to determine one of a number of characteristic properties.

 The word optics is very useful in physics which is related to the reflection of light. The instruments which are used in optics are optical instruments. Thus, the optical instruments are the devices which are used in a various purposes like microscope, telescope, lens, magnifying lens, mirror, astronomical telescope, glass etc. All are used in a different manner like a telescope is used for looking small things bigger. The first optical instruments were telescopes used for magnification of distant images, and microscopes used for magnifying very tiny images. These instruments have been greatly improved and extended into other portions of the electromagnetic spectrum.

 Similar microscopes are used in biology and medicine. Cameras are used by artists. By this we can guess that how much these instruments are useful. These are the best way to observe reality but how do they work? How do they make a small object bigger? How does a mirror form a clear image? What types of lenses are there?

Two Kinds of Optical Instruments. The optical image-forming instruments can be divided into two groups. The first group (projectors) forms real images of an object which is projected onto a screen or photographic plate. This kind of image can be viewed simultaneously by many observers. A motion picture film is a typical example, since everyone in the cinema can simultaneously take in the real image projected on the screen.

 The second group forms virtual images of an object. As a rule, only one observer can see this kind of image, though in the case of a magnifying glass several people can be looking through it at the same time. The virtual image itself is something nonexistent for it is not the rays but their extensions that intersect, and the latter are purely imaginary.

 However, the image becomes a reality as soon as the observer's eye becomes a part of the optical system. The virtual image formed by an instrument is transformed by the eye into the real image projected on the eye's retina. It is no coincidence that optical instruments for a virtual image are sometimes called optical aids. They include magnifying glasses, spectacles, microscopes, and telescopes. Strictly speaking, the observer's eye must always be included in the optical system.

Проверьте, знаете ли Вы следующие слова и словосочетания для понимания текста.

a) Найдите в правой колонке русские эквиваленты:

    1. vision                                    1. испускать, излучать

    2. to exaggerate                        2. рассматривать, считать

    3. to emit                                         3. зрение, восприятие

    4. to differentiate                    4. преувеличивать

    5. to regard                            5. различать, отличать

б) Найдите в правой колонке английские эквиваленты:

    1. воспринимать                    1. to assess

    2. оценить                                       2. to underestimate

    3. мнимое изображение          3. to emphasize

    4. подчеркивать                    4. to perceive

    5. недооценивать                  5. virtual image

THE EYE

 What is the role played by an eye in an optical experiment? Is there a dividing line between the science of vision and the science of light, and what may optics be considered to be after all?

 These questions have always been important to scientists. In the early days of optics the role of the eye was definitely exaggerated, and optics was, in fact, a science of vision. It has to remembered that in those days the eye was believed to emit rays, and the expression “light of my eyes” was taken literally Much later people understood that the role of the eye was to receive the light coming from an object, and still later they began to differentiate between the science of vision and optics which was then regarded as the science of light. Today we are in a position to assess the role of the observer's eye in experimental physics. It is curious, however, that while once the role of the eye used to be exaggerated, we now tend to underestimate it. In any case, a few modern textbooks and teaching aids on physics emphasize the role of the observer's eye in perceiving virtual images. A brief account of how our ideas about the mechanism of vision and the role of the eye have changed with the time will be quite useful. Naturally, they developed as we acquired more knowledge of the structure of the eye. We should therefore get to know what modern ideas are about the anatomy of the human eye.

Проверьте, знаете ли Вы следующие слова и словосочетания для понимания текста.

а) Найдите в правой колонке русские эквиваленты:

        1. to make up                                  1. ударяться, наталкиваться

    2. to bump                                           2. взаимодействовать, влиять друг                                                       на друга

    3. to interact                          3. составлять

    4. composite particle             4. несовместимый

    5. rest mass                            5. составная частица

    6. incompatible                      6. масса покоя

б) Найдите в правой колонке английские эквиваленты:

    1. обнаруживать, открывать     1. to equate

    2. спутывать                                   2. to reveal

    3. приравнивать                     3. to contemplate

    4. переход, превращение      4. to confuse

    5. рассматривать                  5. relativity

    6. относительность               6. conversion

MATTER

 Before the 20th century, the term matter included ordinary matter composed of atoms and excluded other energy phenomena such as light or sound. This concept of matter may be generalized from atoms to include any objects having mass even when at rest, matter does not have a universal definition, nor a fundamental concept in physics today. Matter is also used loosely as a general term for the substance that makes up all observable physical objects.

 All the objects from everyday life that we can bump into, touch or squeeze are composed of atoms. This atomic matter is made up of interacting subatomic particles - usually a nucleus of protons and neutrons, and a cloud of orbiting electrons. Typically, science considers these composite particles matter because they have both rest mass and volume. By contrast, massless particles, such as photons, are not considered matter, because they have neither rest mass nor volume.

 Different fields of science use the term matter in different, and sometimes incompatible, ways. There is no single universally agreed scientific meaning of the word "matter". Scientifically, the term "mass" is well-defined, but "matter" is not. Sometimes in the field of physics "matter" is simply equated with particles that exhibit rest mass, (that cannot travel at the speed of light), such as quarks and leptons.

 Nevertheless, quarks and leptons together make up "ordinary matter", and their interactions contribute to the effective volume of the composite particles that make up ordinary matter.

 Matter commonly exists in four states (or phases): solid, liquid and gas, and plasma. However, advances in experimental techniques have revealed other previously theoretical phases, such as Bose-Einstein condensates and fermionic condensates. A focus on an elementary-particle view of matter also leads to new phases of matter, such as the quark-gluon plasma. For much of the history of the natural sciences people have contemplatedthe exact nature of matter.

 Matter should not be confused with mass, as the two are not quite the same in modern physics. For example, mass is a conserved quantity, which means that its value is unchanging through time, within closed systems. However, matter is not conserved in such systems, although this is not obvious in ordinary conditions on the Earth, where matter is approximately conserved. Still, special relativity shows that matter may disappear by conversion into energy, within such systems. However, as mass (like energy) can neither be created nor destroyed, the quantity of mass and the quantity of energy remain the same during a transformation of matter (which represents a certain amount of energy) into non-material (i.e. non-matter) energy. This is also true in the reverse transformation of energy into matter.