Mayer, Julius

Sec also Carnot, Nicolas Leonard Sadi Clausins, Rudolf Julius Emmanuel Culture and Energy Usage Ethical and Moral Aspects of Energy Use Gibbs, Jonah Willard Industiy and Business, History of Energy Use and Joule, James Prescott Kinetic Energy, Historical Evolution of the Use of Mayer, Julius Robert von Refining, History of Thomson, William Watt, James. 

Mayer, Julius Robert von (1814-1878) German physician and physicist in Heilbronn and one of the founders of thermodynamics. He was the first person to develop the law of the conservation of energy (first law of thermodynamics). 

F. Mayer, Chemie der Organischen Farbstqffe, Julius Springer, Berlin, 1934, p. 103. 

German physician Julius Robert Mayer. Mayer s work, although historically important for its insights into the conservation-of-energy principle, was however tainted by errors in physics and an unacceptable reliance on philosophical arguments. 

The three men whose work later in the nineteenth century was crucial in bringing clarity to this principle were two Germans, the physician Julius Robert Mayer and the great polymath Hermann von Helmholtz, and the British amateur scientist James Joule. In a lecture delivered by Helmholtz on February 7, 1854, in Konigsberg on The Interaction of Natural Forces, ... 

Julius Robert Von Mayer was born in 1814 in Heilbronn, a small town on the Ncckar river, halfway between Heidelberg and Stuttgart. Interested in science as a youth, he decided on a career in medicine, and in 1832 began his medical studies at the University of Tubingen. After completing his studies there in 1838, he received his M.U. degree. 

Cmeva, K. L. (1993). Robert Mayer and the Cnnseivation of Energy. Princeton, NJ Princeton University Press. Friedlander, S. (1905). Julius Robert Mayer. Leipzig T. Thomas. 

Robert Julius Mayer was a physician practicing in Bavaria in the 1840s. As part of his research into human metabolism, he decided to determine the equivalence between heat and work. 

This is the nasty, but inescapable, lesson learned from the Second Law of Thermodynamics, which is derived from Julius Mayer s work. A few examples will suffice to close this chapter ... 

Figure 3.40 Julius Lothar Mayer (1830-1895), who pointed out that triads of elements, such as lithium, sodium, and potassium, and magnesium, calcium, and strontium, had similar chemical properties. He independently formulated the periodic law of the elements at about the same time as Mendeleev. (Published with permission from the Deutsches Museum, Munich.)...

Note that the effect is very small, when an apparatus is used as in the numeric example. Actually, the units in the equation do not cancel, but we can introduce cal = X J. We should obtain X = 4.18. Joule recovered this ratio in all his experiments. Already Carnot gave in his posthumous published work a remarkable accurate numerical value for the mechanical heat equivalent and even before Joule, Robert Julius Mayer succeeded in this problem. 

Julius Robert Mayer formulates the mechanical equivalent of heat... 

Julius von Mayer plants transform hght into chemical energy... 

These results are in accord with the first law of thermodynamics, whose discoverer Julius von Mayer postulated in 1842 that plants take up energy in the form of light and that they transform it into another, chemical state of energy (Mayer 1845). In 1872 Eduard Pfliiger defined respiration as a process located on the cellular level (Pfiiiger 1872). 

Julius Robert von Mayer (1814-1878) German physician and physicist Tubingen, Germany. 

In the early 19th century (1803), Dalton proposed his atomic theory. In 1811, Amedeo Avogadro made clear the distinction between atoms and molecules of elementary substances, hi addition, the concepts of heat, energy, work, and temperature were developed. The first law of thermodynamics was set forth by Julius Robert von Mayer and the second law of thermodynamics was postulated by Rudolf Julius Emanuel Clausius and William Thomson (Lord Kelvin). Later in the century, Clausius, Ludwig Boltzmarm, and James Clerk Maxwell related the ideal gas law in terms of a kinetic theory of matter. This led to the kinetics of reactions and the laws of chemical equilibrium. 

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