André-Marie Ampère

André-Marie Ampère
André-Marie Ampère (1775-1836)
Born	January 22 1775 Polémieux, Lyon, France
Died	June 10, 1836 Marseille, France
Residence	France
Nationality	French
Field	Physicist
Institutions	Bourg-en-Bresse École Polytechnique
Known for	Ampere's Law

André-Marie Ampère (January 20 1775 – June 10 1836), was a French physicist who is generally credited as one of the main discoverers of electromagnetism. The SI unit of measurement of electric current, the ampere, is named after him.

Early days

Ampère was born near Lyon, France, and lived from 1782 to 1797 in the nearby burg of Poleymieux-lès-Monts-d'Or. As a child prodigy, he took a passionate delight in the pursuit of knowledge from his very infancy, and is reported to have worked out long arithmetical sums by means of pebbles and biscuit crumbs before he knew the figures. It is also said that he read the entire contents of an encyclopedia at a very early age. His father began to teach him Latin, but ceased on discovering the boy's greater inclination and aptitude for mathematical studies. The young Ampère, however, soon resumed his Latin lessons, to enable him to master the works of Euler and Bernoulli.

In later life he was accustomed to say that he knew as much about mathematics when he was eighteen as ever he knew; but, a polymath, his reading embraced nearly the whole round of knowledge — history, travels, poetry, philosophy and the natural sciences. His father was executed during the French Revolution, and this had a deeply disturbing, if temporary, effect on Ampere.

In 1796 he met Julie Carron, and an attachment sprang up between them. In 1799 they were married. From about 1796 Ampère gave private lessons at Lyons in mathematics, chemistry and languages; and in 1801 he removed to Bourg, as professor of physics and chemistry, leaving his ailing wife and infant son (Jean Jacques Ampère) at Lyon. In 1802, Ampere published his first paper on probability theory. She died in 1804, and he never recovered from her death. In the same year he was appointed professor of mathematics at the lycée of Lyon.

According to the Catholic Encyclopedia, Ampere used to say that "at eighteen years he found three culminating points in his life, his First Communion, the reading of Thomas's "Eulogy of Descartes," and the taking of the Bastille... On the day of his wife's death he wrote two verses from the Psalms, and the prayer, 'O Lord, God of Mercy, unite me in Heaven with those whom you have permitted me to love on earth.' Serious doubts harassed him at times, and made him very unhappy. Then he would take refuge in the reading of the Bible and the Fathers of the Church." [1]

Contributions to physics and further studies

Ampere's work on probability attracted the attention of some of the important mathematicians of the day, and through it he obtained recommendations for the Lyon appointment, and afterwards (1804) a subordinate position as lecturer on mathematical anaysis in the polytechnic school at Paris. He was later appointed professor of mathematics in 1809. Here he continued to pursue his scientific research and his diverse studies with unabated diligence. He was admitted as a member of the French Academy in 1813, replacing Joseph Louis Lagrange, who had died that year.

Ampère's fame mainly rests on the service that he rendered to science in establishing the relations between electricity and magnetism, and in developing the science of electromagnetism, or, as he called it, electrodynamics. On September 11, 1820 he heard of H. C. Ørsted's discovery that a magnetic needle is acted on by a voltaic current. Only a week later, on September 18, he presented a paper to the Academy containing a far more complete exposition of that and kindred phenomena.

His primary contribution was to demonstrate a force between two conductors carrying an electric current, and to establish a mathematical expression for the forces consistent with the experimental determination of that attraction. He showed that two wire conductors running parallel to each other and carrying currents running in the same direction exert a force of attraction on each other. When the current of one of these wires is reversed, the two wire conductors exert a repulsive force. Ampere also developed a primitive galvanometer, which could be used to measure the quantity of current passing through a circuit due to the magnetic forces generated between the current in the galvanometer and the current in the conductor to be tested.

Legacy and final days

The whole field thus opened up he explored with characteristic industry and care, and developed a mathematical theory which not only explained the electromagnetic phenomena already observed but also predicted many new ones.

In 1826, Ampere published a complete description of his theory, taking into consideration the efforts of other scientists since he first put forward his analysis in 1820.

After about three years of writing on electrical subjects, he became interested in the organization of all the bodies of knowledge, and dedicated most of the rest of his life to this subject. This work did not profoundly affect the world of science the way his mathematical and experimental researches in electricity had.

In the spring of 1836, He became ill on a trip from Paris to Marseilles. His faith had always been a strong point in his life, plagued as it was by his own eccentricities as well as by the traumatic incidents of his life.

He died at Marseille and is buried in the Cimetière de Montmartre, Paris. The great amiability and childlike simplicity of Ampère's character are well brought out in his Journal et correspondence (Paris, 1872).

See also

• Ampere's Law
• Electricity
• Magnetism

Notes

• This article incorporates text from the Encyclopædia Britannica Eleventh Edition, a publication now in the public domain.

References

ISBN links support NWE through referral fees

<<This article needs at least 3 reliable references, properly formatted.>> The Eclectic Magazine of Foreign Literature, Science and Art, Jan.-Apr. 1856, WH Bidwell, Ed. and Proprietor, New York. "Men of Science" p. 90-104.

p. 546, Note F., Note relative to the Calculation of the mutual Action of Electric Currents, in A Treatise on Electricity in Theory and Practice, by Aug. De La Rive, 2 Vols. London: Longman, Brown, Green and Longman, 1853.

p5

Encyclopaedia Metropolitana, or, Universal Dictionary of Knowledge. Ed. The Rev. Edward Smedley, Hugh James Rose, Henry John Rose B. Fellows et al., London. p 5. Vol IV<<The following reference needs proper formatting:>>

• Williams, L. Pearce. (1970). "Ampère, André-Marie". Dictionary of Scientific Biography 1: 139-147. New York: Charles Scribner's Sons.

External links

• Ampere and the history of electricity (Correspondence, bibliography, experiments, simulations, etc., edited by CNRS, France)
• Ampere's Museum (CNRS) is in Poleymieux-au-Mont-d'or, near Lyon, France
• John J. O'Connor and Edmund F. Robertson. André-Marie Ampère at the MacTutor archive
• Eric W. Weisstein, Ampère, André (1775-1836) at ScienceWorld.
• Catholic Encyclopedia on André Marie Ampère

Credits

New World Encyclopedia writers and editors rewrote and completed the Wikipedia article in accordance with New World Encyclopedia standards. This article abides by terms of the Creative Commons CC-by-sa 3.0 License (CC-by-sa), which may be used and disseminated with proper attribution. Credit is due under the terms of this license that can reference both the New World Encyclopedia contributors and the selfless volunteer contributors of the Wikimedia Foundation. To cite this article click here for a list of acceptable citing formats.The history of earlier contributions by wikipedians is accessible to researchers here:

• André-Marie_Ampère  ^history

The history of this article since it was imported to New World Encyclopedia:

• History of "André-Marie Ampère"

Note: Some restrictions may apply to use of individual images which are separately licensed.