File:Faradays transformer.png

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Summary

DescriptionFaradays transformer.png	English: Drawing of the first transformer, built by British scientist Michael Faraday in the 1830s. It consisted of an iron ring with two windings of insulated wire around it. Faraday attached one winding to a sensitive galvanometer. When he touched the other winding to a single cell battery, the winding created a changing magnetic field in the ring which induced a momentary current in the second winding due to electromagnetic induction, which was registered by the galvanometer. Although this device looks remarkably like a modern transformer, Faraday is not considered the inventor of the transformer. He only applied individual pulses of current to his device, not the alternating current that allows modern transformers to work continuously. More importantly the device had the same number of turns on both windings. Faraday did not discover the principle that makes transformers useful - that it can be used to transform the voltage up or down by using different numbers of turns in the seconday than in the primary winding.
Date	1896
Source	Downloaded 2009-08-06 from Frederick Bedell (1868-1958), 1896, The Principles of the Transformer, The MacMillan Co., New York, p. 288, fig. 162. High resolution version from Friedrich Uppenborn (1859-1907), 1889, History of the Transformer, p 3, fig 2.
Author	Unknown authorUnknown author
Permission (Reusing this file)	Public domain - published at least 114 years ago

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File history

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	Date/Time	Dimensions	User	Comment
current	17:41, 3 September 2011	1,484 × 1,568 (3.15 MB)	DrJunge	New scan, denoised, contrast adjusted.
	15:46, 23 August 2011	848 × 861 (978 KB)	Wdwd	Higher resolution Taken from: Author: Uppenborn, Friedrich, 1859-1907 Title: Electric transformers -- History Online: http://www.archive.org/details/historyoftransfo00upperich
	07:49, 27 January 2011	653 × 652 (67 KB)	Chetvorno	{{Information \|Description={{en\|Drawing of the first Wikipedia:transformer, built by British scientist Michael Faraday in the 1830s. It consisted of an iron ring with two windings of insulated wire around it. Faraday attached one winding to a sensi