Sergey Alexeyevich Chaplygin (russian: Серге́й Алексе́евич Чаплы́гин; 5 April 1869 – 8 October 1942) was a Russian and

Soviet The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, ...

physicist A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate caus ...

, mathematician, and mechanical

engineer Engineers, as practitioners of engineering, are professionals who invent, design, analyze, build and test machines, complex systems, structures, gadgets and materials to fulfill functional objectives and requirements while considering the l ...

. He is known for mathematical formulas such as

Chaplygin's equation In gas dynamics, Chaplygin's equation, named after Sergei Alekseevich Chaplygin (1902), is a partial differential equation useful in the study of transonic flow. It is : \frac + \frac\frac+v \frac=0. Here, c=c(v) is the speed of sound, determined ...

and for a hypothetical substance in cosmology called Chaplygin gas, named after him. He graduated in 1890 from Moscow University, and later became a professor. He taught mechanical engineering at Moscow Higher Courses for Women in 1901, and of applied mathematics at Moscow School of Technology, 1903. He was appointed Director of the courses in 1905. Leonid I. Sedov was one of his students. Chaplygin's theories were greatly inspired by Nikolay Yegorovich Zhukovsky, N. Ye. Zhukovsky, who founded the TsAGI, Central Institute of Aerodynamics. His early research consisted of hydromechanics. His "Collected Works" in four volumes were published in 1948.

Honours and awards

* Hero of Socialist Labour (1 February 1941) * Two Orders of Lenin (1 February 1941 and 22 December 1933) * Order of the Red Banner of Labour, twice (10 July 1927 and ?) * Nikolay Yegorovich Zhukovsky, Zhukovsky Prize (1925) Chaplygin was elected to the Russian Academy of Sciences (the Academy of Sciences of the USSR in 1925-1991) in 1924. The lunar crater Chaplygin (crater), Chaplygin and town Chaplygin, Lipetsk Oblast, Chaplygin are named in his honour.

External links

* {{DEFAULTSORT:Chaplygin, Sergey Alexeyevich 1869 births 1942 deaths People from Chaplygin Mathematicians from the Russian Empire Heroes of Socialist Labour Recipients of the Order of Lenin Full Members of the USSR Academy of Sciences Corresponding Members of the Russian Academy of Sciences (1917–1925) Moscow State University alumni Physicists from the Russian Empire Soviet mathematicians Soviet physicists 19th-century mathematicians from the Russian Empire 20th-century Russian mathematicians 20th-century Russian physicists Russian mechanical engineers Soviet mechanical engineers Engineers from the Russian Empire Central Aerohydrodynamic Institute employees

Honours and awards

See also

External links