In the early 1830s, Michael Faraday performed his seminal experimental research on electromagnetic induction, in which he created the first electric dynamo---a machine for continuously converting rotational mechanical energy into electrical energy. His machine was a conducting disc, rotating between the poles of a permanent magnet, with the voltage/current obtained from brushes contacting the disc. In his first dynamo, the magnetic field was asymmetric with respect to the axis of the disc. This is to be contrasted with some of his later symmetric designs, which are the ones almost invariably discussed in textbooks on electromagnetism. In this paper, a theoretical analysis is developed for Faraday's first dynamo. From this analysis, the eddy currents in the disc and the open-circuit voltage for arbitrary positioning of the brushes are determined. The approximate analysis is verified by comparing theoretical results with measurements made on an experimental recreation of the dynamo. Quantitative results from the analysis are used to elucidate Faraday's qualitative observations, from which he learned so much about electromagnetic induction. For the asymmetric design, the eddy currents in the disc dissipate energy that makes the dynamo inefficient, prohibiting its use as a practical generator of electric power. Faraday's experiments with his first dynamo provided valuable insight into electromagnetic induction, and this insight was quickly used by others to design practical generators.
...MoreSimilar Citations
Article
Cobb, Aaron D.;
(2009)
Michael Faraday's “Historical Sketch of Electro-Magnetism” and the Theory-Dependence of Experimentation
(/isis/citation/CBB001230094/)
Article
Cobb, Aaron D.;
(2011)
History and Scientific Practice in the Construction of an Adequate Philosophy of Science: Revisiting a Whewell/Mill Debate
(/isis/citation/CBB001024143/)
Book
Forbes, Nancy;
Mahon, Basil;
(2014)
Faraday, Maxwell, and the Electromagnetic Field: How Two Men Revolutionized Physics
(/isis/citation/CBB001551506/)
Article
Cavicchi, Elizabeth;
(2006)
Nineteenth-Century Developments in Coiled Instruments and Experiences with Electromagnetic Induction
(/isis/citation/CBB000671003/)
Book
Bruce J. Hunt;
(2021)
Imperial Science: Cable Telegraphy and Electrical Physics in the Victorian British Empire
(/isis/citation/CBB544275565/)
Book
Steinle, Friedrich;
(2005)
Explorative Experimente: Ampère, Faraday und die Ursprünge der Elektrodynamik
(/isis/citation/CBB001033912/)
Chapter
Steinle, Friedrich;
(2009)
How Experiments Make Concepts Fail: Faraday and Magnetic Curves
(/isis/citation/CBB001020629/)
Book
Fisher, Howard J.;
(2001)
Faraday's Experimental Researches in Electricity: Guide to a First Reading
(/isis/citation/CBB000100209/)
Book
Faraday, Michael;
(2000)
Experimental Researches in Electricity
(/isis/citation/CBB000100206/)
Thesis
Zito, Fredrick Anthony;
(2002)
Maxwell, Hertz, and Marconi: Using the History of Science and Technology in Science Education
(/isis/citation/CBB001562545/)
Book
Faraday, Michael;
(2000)
Experimental researches in electricity
(/isis/citation/CBB000111843/)
Article
Li, Guo-feng;
(2007)
The dissemination of Faraday's electromagnetic knowledge in late Qing Dynasty China
(/isis/citation/CBB000701115/)
Article
Franco Bagnoli;
Roberto Livi;
(2018)
Michael Faraday: A virtuous life dedicated to science
(/isis/citation/CBB210260075/)
Article
Wang, Luoyin;
Hu, Huakai;
Sun, Hongqing;
(2009)
The Formation Process of Faraday's Thought of Lines of Force
(/isis/citation/CBB000933755/)
Chapter
Salvo D'Agostino;
(2016)
What is light? What is ether? An overwiew of Einstein’s problem on the abolition of ether and on its inheliminable presence in General Relativity
(/isis/citation/CBB336368332/)
Article
Wang, Luoyin;
Hu, Huakai;
(2008)
Faraday's Research on Electromagnetic Rotation
(/isis/citation/CBB000933540/)
Book
Herr, Wiebke;
(2012)
Spät und scheinbar plötzlich: zu den Hintergründen des markanten Etablierungsverlaufs der Elektrizität (1730--1748)
(/isis/citation/CBB001420987/)
Article
Silva, Cibelle Celestino;
(2007)
The Role of Models and Analogies in the Electromagnetic Theory: A Historical Case Study
(/isis/citation/CBB001032896/)
Article
Wiederkehr, Karl Heinrich;
(2010)
Über Vorstellungen von der elektrischen Leitung, die Entwicklung einer Elektronentheorie der Metalle und der Beginn einer Festkörperphysik
(/isis/citation/CBB001034841/)
Thesis
Cameron Lazaroff-Puck;
(2021)
What Theories Are Made Of: How Industry and Culture Shaped Maxwell's Theories of Electromagnetism
(/isis/citation/CBB411319578/)
Be the first to comment!