Part II section I

Introduction into mechanics

Read and remember the pronunciation of the following words

mechanics [mI'kænIks] branch [bra:nt∫] physics ['fIzIks] engineering [,endʒ I'nI∂ rIŋ] rigid ['rIdʒ Id]

fluid ['flu: Id] structure [str ʌ kt∫∂] machine [m∂ '∫I:n] division [dI'vIʒ n] distinguish [dI'stIŋgwI∫]

phenomena [f∂'n ɔ mIn∂] dynamics [daI'næmIks] associate [∂'sou∫IeIt] mathematician [,mæθ∂m∂'tI∫n] engine ['endʒ In]

What is mechanics? Mechanics is the branch of physics and engineering which deals with the interrelations of force, matter and motion. It is divided into three parts: mechanics of rigid bodies, mechanics of deformable bodies, and mechanics of fluids.

The mechanics of rigid bodies is subdivided into static’s and dynamics, the former dealing with bodies at rest, the latter with bodies in motion. All the structures and machines are never absolutely rigid and deform under the loads to which they are subjected. All these processes are considered by the second division of mechanics. The third division of mechanics, the mechanics of fluids, is subdivided into the study of incompressible fluids and compressible ones.

The students should distinguish the difference between theoretical mechanics and applied mechanics. The former comprises the sum of exact laws and principles that have been mathematically deducted from certain fundamental facts, the latter consists of the application of these laws to the design of structures and machines.

Mechanics is a physical science, since it deals with the study of physical phenomena. The part of mechanics is dynamics, dealing with the analyses of bodies in motion.

Although the study of mechanics goes back to the time of Aristotle (384 – 322 B.C. (before Christ – до нашей эры) and Archimedes (287 – 212 B.C.), one had to wait until Newton (1642 – 1727) to find a satisfactory formulation of its fundamental principles. Their validity had remained unchallenged until Einstein formulated his theory of relativity in 1905. While its limitations have now been recognized, Newtonian mechanics still remains the basis of today’s engineering sciences. The basic concepts used in mechanics are space, time, mass and force.

There are a lot of scientist closely associated with the development of mechanics – Jan Leron D’Alembert (Жан Лерон Д’Аламбер (1717 – 1783), French mathematician, physicist and philosopher; Joseph Lui Lagrange (Жозеф Луи Лагранж (1736 – 1813), outstanding French mathematician and mechanic; William Rouan Hamilton (Вильям Роуан Гамильтон (1805 – 1865), English mathematician; Michael Vassileyevitch Lomonosov (Михаил Васильевич Ломоносов (1711 – 1765), famous Russian scientist, a naturist, philosopher, historian; Isaak Newton (Исаак Ньютон (1642 – 1727), famous English physicist and mechanic; Albert Einstein (Альберт Эйнштейн (1879 – 1955), world – known German scientist, mathematician, physicist; Robert Hooke (Роберт Хук), the English scientist who formulated in 1678 the law of elasticity.

Some other names of Russian scientists and inventors, dealing with mechanics should be mentioned here: I.I. Polzunov (1728 – 1766), the inventor of the first steam engine; A.N. Nartov (1684 – 1756), the inventor of the first lathe, working in the field of applied mechanics; M.V. Ostrogradsky (1801 – 1856), one of the founders of analytical mechanics; P.S. Chebishev, the founder of the Russian school of theory of mechanisms; professor Zhukovsky (1847 – 1921) and K.E. Tsiolkovsky (1857 – 1935), both dealing with mechanics of moving bodies.

1. Remember the meanings of the words

fluid – жидкость

the former …, the latter … – первый (упомянутый) …, последний …

compressible – сжимаемый

to distinguish – различать

applied mechanics – прикладная механика

to recognize – признавать.

2. Read the following verbs and pay attention to the prepositions used after them

to consist of – состоять из …

to deal with – иметь дело с чем-либо

to divide into – делить на …

to subject to – подвергать чему-либо

to deduct from – выводить, заключать, делать заключение из чего-либо

to associate with – связывать с чем-либо.

3. Look through the text to find the English equivalents of the following words and give the sentences with them

иметь дело с чем-либо; подвергать нагрузкам; подразделять; применение законов; обоснованность; обоснование; механика жидкостей.

4. Finish the sentences

1. Mechanics deals with …

2. All the bodies deform under loads …

3. Mechanics of fluids study …

4. There are three subdivisions of mechanics …

5. The applied mechanics concerns …

6. The part of mechanics is dynamics …

7. Newton’s laws of mechanics still remain …

8. The basic concepts of mechanics are …

9. A number of Russian and foreign scientists are closely associated with …

10. The inventor of the first lathe is …

11. It was Newton who formulated …