Moritz von Jacobi
German engineer and physicist (1801–1874)
Moritz Hermann von Jacobi (German: [ˈmoːʁɪts fɔn
jaˈkoːbi]; 21 September 1801 – 10 March 1874), also known as Boris Semyonovich Yakobi (Russian: Борис Семёнович Якоби), was a German-Russian electrical engineer and physicist.
Motors
Jacobi began to study magnetic motors in 1834. In 1835 moved to Dorpat (now Tartu, Estonia) to lecture at Dorpat University. He moved to Saint Petersburg in 1837 to research the usage of electromagnetic forces for moving machines at the Russian Academy of Sciences. He investigated the power of an electromagnet in motors and generators. While studying the transfer of power from a battery to an electric motor, he deduced the maximum power theorem. Jacobi tested the output of motors by determining the amount of zinc consumed by the battery. With the financial assistance of Tsar Nicholas I, in 1839 Jacobi constructed a 28-foot electric motor boat powered by battery cells, which carried 14 passengers on the Neva river against the current at three miles per hour.
Jacobi's law
The law known as the maximum power theorem states:
Maximum power is transferred when the internal resistance of the source equals the resistance of the load, when the external resistance can be varied, and the internal resistance is constant.
The transfer of maximum power from a source with a fixed internal resistance to a load, the resistance of the load must be the same as that of the source.
The public source identifies “Moritz von Jacobi” as german engineer and physicist (1801–1874). This brief keeps that definition visible, then builds a research path around Moritz, Jacobi and German.
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Biographical claims are most persuasive when dates, appointments and relationships can be traced to records created close to the events described. The source revision retrieved here is dated Aug 29, 2026. The linked authority identifier is Q60579. VIAF identifies the subject as 2313155. The Library of Congress control number is nr89003445. 4 of 4 selected statements include explicit references; 0 carry qualifiers and 1 use preferred rank. The first chronological checks are 1801, 1874, 1834 and 1835.
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This entry incorporates text from “Moritz von Jacobi” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.