Rudolf Clausius: biography and contributions of this German physicist and mathematician

Considered one of the founding fathers of thermodynamics, Rudolf Clausius is one of the leading figures not only in 19th century German physics, but also in European science of his century.

Very skilled in both physics and mathematics, he was an example to be followed by other scientists such as the Scotsman James Maxwell, one of the scholars of electromagnetic theory.

Below you will find a biography of Rudolf Clausius in which we will see what were his main contributions to the field of physics.

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Short biography of Rudolf Clausius

Rudolf Clausius was a German physicist and mathematician known for being one of the founders of thermodynamics, being he who formulated the second of the laws that make up these principles. He, along with other illustrious figures such as the British physicists William Thomson, Lord Kelvin and James Joule, developed these laws. physics, being the French physicist Nicolas Léonard Sadi Carnot who is credited with having raised the first of the laws of thermodynamics.

The most relevant studies by Rudolf Clausius dealt with the effect of heat on different fluids and materials, raising the kinetic theory on the behavior of atoms and molecules.

Birth and early years

Rudolph Julius Emmanuel Clausius was born on January 2, 1822 in Köslin, Prussia, present-day Koszalin, Poland. His father was a Protestant and ran a small school where young Rudolf Clausius would attend during his early formative years.

Later he he entered the gymnasium (German lyceum) of the city of Stettin, presently Szczecin in Poland, where he would continue his education.

University education

In 1840 he entered the University of Berlin. There he began to attend history classes, but soon switched to science and was taught by physicist Georg Simon Ohm and mathematician Richard Dedekind.

Studying mathematics and physics, Clausius discovered that they were branches of knowledge that were given to them especially well, making them definitely his profession when he finished studying in Berlin in 1844.

Later Clausius he studied at the University of Halle, obtaining there a doctorate in physics in 1847 thanks to his work on the optical effects that occur on planet Earth as a consequence of the existence of the atmosphere. Although this work presented some errors in terms of approach, it served Clausius to show that he possessed great gifts for mathematics and physics, making himself a renown among the scientific community German.

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First scientific investigations

Rudolf Clausius's first experimental ventures began in 1849 with the study of the laws governing the relationships between pressure and temperature. Subsequently he would dedicate himself to the study of different substances and at what temperature they take to boil, drawing the first boiling curves.

His life would begin to take on special relevance in the scientific field of his country from 1850, when he obtained a position as professor of physics at the Royal School of Engineering and Artillery in Berlin, where he would remain until 1855. In addition to this position, Rudolf Clausius also served at the University of Berlin as a privatdozent, a professor who could teach at the university but that his fees were paid directly by his students rather than by the institution.

The highlight of this period in the life of Rudolf Clausius was the publication in 1850 of what would be his most important work: "On the forces of movement caused by heat".

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Developing the kinetic theory

In 1855 Clausius left Germany and obtained a teaching position at the Swiss Federal Institute of Technology in Zurich. Two years later he focused on studying in the field of kinetic theory, experimented at this time with the concept of the "free mean path of a particle", a term that refers to the distance between two encounters, one after the other, of the molecules that make up a gas. This contribution by Clausius would be very relevant to the field of physics of his time.

Rudolf Clausius would remain at the Swiss Federal Institute of Technology for several years, where he would teach physics classes. He would change places in 1867, moving to Würzburg, where he would also work as a teacher until 1869 and obtaining a membership in the Royal Society of London in 1868, because his fame and his research were already known at the European level. He would go to the University of Bonn to teach physics classes, an institution in which he would work for the rest of his life.

Precisely working in Bonn when, at the age of 50, the Franco-Prussian War broke out (1870-1871). During the conflict he organized, together with several of his students, a volunteer ambulance corps. As a result of his involvement in the war, Clausius suffered a leg injury, which caused him great discomfort for the rest of his life. However, the injury brought him recognition in German society and, thanks to his heroic action, Rudolf Clausius received the Iron Cross.

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Last years and death

During the last years of his life, Rudolf Clausius dedicated himself to his children and put research aside a little.. Furthermore, with the war wound sustained during the war he could not move easily, causing him to prefer to stay in Bonn rather than travel as much as he had done in youth. Nevertheless, Clausius continued teaching at the University of Bonn until his death.

Rudolf clausius he died on August 24, 1888 in Bonn, Germany, at the age of 66. His first wife, Adelheid Rimpau, had died in 1875, leaving him in the care of his six children, and Clausius remarried in 1886, this time to Sophie Stack with whom he had a son.

Acknowledgments to this physicist and mathematician

In 1870 Rudolf Clausius obtained the Huygens Medal and, in 1879, he received the Copley Medal., recognition given by the Royal Society of London to those who have made important contributions in the field of biology or physics.

In the year 1878 was appointed a member of the Royal Swedish Academy of Sciences and, in 1882, he was awarded an honorary doctorate by the University of Würzburg. In 1883 he received the Poncelet Prize, awarded by the French Academy of Sciences to all scientists who have made significant contributions to science in general. Rudolf Clausius has continued to receive honors long after his death. In 1935 he named a crater on the Moon with his surname: the Clausius crater.

Scientific contributions of Rudolf Clausius

There are several contributions that Rudolf Clausius made to physics. Next we will see what are the most remarkable aspects of his discoveries and theories.

Kinetic theory of gases

In 1857 he published the first complete theory on the kinetic theory of matter.. For this he used statistical mechanics, establishing an ideal model for the structure of gases. Applying laws of mechanics, Clausius deduced the external or macroscopic behavior of these gases based on hypotheses about the statistical behavior of the molecules of these fluids.

He deduced that, because molecular collisions occur between molecules in motion and with elasticity, at each instant there will be molecules inside the gas moving in all directions and at all possible speeds. The total energy of translation of these molecules gives the measure of the caloric content of the gas, and their kinetic energy depends directly on the temperature of the gas.

Clausius's work on the individual molecules of gases is considered to be crucial for the conception of the kinetic theory of gases. The kinetic theory was originally developed by James Maxwell in 1859, but based very notoriously on the work of Rudolf Clausius.. Curiously, this same theory was criticized by Clausius, something that served Maxwell to update his kinetic theory in 1867.

Another of Clausius's contributions in this field was to develop a criterion to differentiate between atoms and molecules. According to him, gas molecules were complex bodies, with constituent parts that move. Today, the idea of ​​a molecule is a particle made up of other atoms, something very common in gases such as oxygen, nitrogen or hydrogen and also other substances such as water or ozone.

Second law of thermodynamics

Along with other great scientists of his time, Rudolf Clausius is considered one of the founding fathers of thermodynamics. He is credited with the proposition of the second law of these principles that says that heat can never pass by itself from a colder body to a warmer one.

This principle, also called the entropy principle, a concept that he himself introduced and defined in 1865, affirms that, in practice, the step process technique The heat of a body at a higher temperature than another that is at a lower temperature cannot be carried out in an inverse way without permanent modifications in the environment.

One of the deductions from this principle is that the energy released when the temperature drops from one Ta value to another Tb is that it is not completely transformed into mechanical energy, and the energy efficiency of this transformation is at most 1-Tb / Ta. This solved one of the main problems of the physics of his time, with scientists who theorized about whether or not it was possible to fully convert heat energy into work mechanic.