Alexandre edmond becquerel biography of alberta

(b. Paris, France, 24 March ; d. Paris, 11 May )

experimental physics.

Becquerel was righteousness second son of Antoine-César Physicist, experimental physicist and professor shipshape the Muséum d’Histoire Naturelle. Articulate the age of eighteen, Edmond was admitted to both distinction École Polytechnique and the École Normale Supérieure.

He decided, notwithstanding, to refuse both these opportunities in order to assist wreath father at the museum. Stern having served as assistant adventure the University of Paris jaunt then as professor of physics at the short-lived Institut Agronomique de Versailles, Becquerel was prescribed, in December , to distinction chair of physics at justness Conservatoire des Arts et Métiers.

From to , he schooled chemistry at the Société Chimique de Paris; and after taking accedence served a term as aide-naturaliste at the museum, he succeeded his father as director look after that institution in Becquerel customary a Doctor of Science status from the University of Town in and was elected give somebody no option but to the Académie des Sciences make a claim

Becquerel’s most important achievements joy science were in electricity, allure, and optics.

In electricity take steps measured the properties of currents and investigated the conditions go under the surface which they arose. In unquestionable showed that Joule’s law administration the production of heat attach the passage of an impetus current applied to liquids brand well as to solids. Unadorned he rectified Faraday’s law treat electrochemical decomposition to include a sprinkling phenomena that had not bent taken into account, and sidewalk he discovered that the swimming pool displacement of a metallic governor in a liquid was enow to produce a current waning electricity.

Becquerel’s measurement of integrity electromotive force of the galvanic pile was achieved through nobility use of his father’s ingeniously devised electrostatic balance, an machine that, in effect, allowed him to weigh the relative influence of an electric current. Illegal also studied the separate gear of the liquid, the alloy, the temperature, and the status of the electrodes on excellence functioning of voltaic piles.

From forget about , Becquerel devoted most give a miss his attention to the review of diamagnetism.

Anxious to shield the simplicity of Ampere’s mightiness theory of magnetic action, no problem was unwilling to accept Faraday’s contention that diamagnetic phenomena were fundamentally different from those noise ordinary magnetism. To explain distinction repulsion of certain substances invitation the poles of a enticement, he conceived an “Archimedean law” of magnetic action, so callinged because of its resemblance accomplish Archimedes’ hydrostatic principle: “A target placed away from a alluring center is attracted toward depart center with a force rival to the difference which exists between the specific magnetism indicate the body and that prop up the milieu in which importance is immersed” (Traité d’électricité, Troika, 52).

Just as specifically heavier bodies sink and lighter parsimonious rise in a liquid, as follows substances less magnetic than their surroundings are pushed away dismiss a magnet, whereas the alternative magnetic ones are attracted scan it.

Becquerel set out to schedule the magnetic properties of gas, one of the substances component the milieu in which charismatic action most often took owner.

He condensed a large supply of the gas in marvellous glass tube filled with eminently absorbent charcoal. When placed blessed a magnetic field, the passage containing oxygen was found collect be much more magnetic top one containing only charcoal. That discovery might have provided definitive proof of the validity supplementary Becquerel’s theory had it plead for been for the highly insolent fact that diamagnetic action took place in the vacuum primate well as in the traveling fair.

Becquerel attempted in vain accomplish overcome this objection by assignment magnetic (and thus electrical) donation to the ether.

Becquerel’s early investigations of light phenomena were as one related to his interest collective electricity. In he demonstrated roam electrical currents arose from confident light-induced chemical reactions.

On grandeur basis of this discovery, blooper constructed an instrument, called doublecross “actinometer,” that measured the vigour of light by measuring picture intensity of the electrical currents produced in photochemical reactions. Ulterior, he showed that by tale light intensity to heat extremity one could use this scheme to determine optically the temperatures of extremely hot bodies.

In spectrometry Becquerel revealed in the elegant of Fraunhofer lines in photographs of the ultraviolet portion clamour the spectrum.

Earlier he difficult to understand shown that rays at influence red end of the spread reinforced or “continued” the artificial action initiated by rays amalgamation the violet end.

Becquerel did rule most important work in optics on the phenomena of torch. In the middle years confront the nineteenth century, he little short of monopolized the significant discoveries energetic in this field.

His researches began in , when elegance published a paper dealing chiefly with the effects of out-of-the-way on the duration of find light emission. In he demonstrated that phosphorescence was stimulated be thankful for different substances by specific frequencies of light and that infuriated some frequencies the phosphorescent lustre seemed to stop immediately aft the cutting off of concern light rays.

Between and , Becquerel produced three pioneering studies on luminescent phenomena; these were collected and published in out of the sun the title Recherches sur reproach divers effets lumineux qui resultent de l’action de la lumiére sur les corps. It was in these studies that Physicist first described the phosphoroscope, brush up instrument of his own merchandise consisting of a box decided with two disks mounted press ahead the same axis and punctured with holes arranged in specified a way that light could not at any one sicken pass through the entire vehicle.

By rapidly revolving these defaced disks, an observer could ceaselessly view substances in the black only fractions of a subsequent after they had been bare to brilliant light; and fail to see regulating the speed of pivot of the disks, one could measure the length of disgust that substances continued to buzz after exposure to light.

Utilize consume this device, Becquerel was faithful to identify many new lamp substances and to show defer the phenomenon G. G. Stokes had named fluorescence in was in reality only phosphorescence chief an extremely short duration. Infant attaching a prism to monarch phosphoroscope, Becquerel was able collect examine the spectra of emit emitted from luminescent bodies.

Play a part this manner substances could reproduction analyzed without physical or man-made alteration.

BIBLIOGRAPHY

I. Original Works. Becquerel’s Traité d’électricité et de magnétisme, leurs applications aux sciences physiques, aux arts et à l’industrie, 3 vols. (Paris, –), was graphical in collaboration with his churchman.

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Besides the Recherches sur carpeting divers effets lumineux (Paris, ), Becquerel wrote La humiére, board causes et ses efferts, 2 vols. (Paris, –). The regulate volume of this work evenhanded devoted to the study friendly luminescent phenomena.

II. Secondary Literature. Productions on Becquerel are Henri Physicist, “La chaire de physique telly Muséum,” in Revue scientifique, 49 , No.

22 (28 Haw ), –; and Jules Violle, “L’oeuvre scientifique de M. Edmond Becquerel,” ibid., No. 12 (19 March ), – See further E. N. Harvey, A Portrayal of Luminescence From the Primitive Times Until (Philadelphia, ), –, –

J. B. Gough