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Hopkinson writes: 'The transformers considered are those having a continuous iron magnetic circuit of uniform section. Let A be area of section of the core, m and n the number of convolutions of the primary and secondary coils respectively, R, r, and ρ their resistances, ρ being the resistance of the secondary external to the transformer, x and y currents in the two coils, a induction per square centimetre, α the magnetic force, l the length of the magnetic circuit, E = B sin 2π (t/T), the difference of potentials between the extremities of the primary, T being the periodic time.'

Annotations in pencil and ink throughout. Includes three geometrical diagrams.

Subject: Physics

Received 17 February 1887. Read 10 March 1887.

A version of this paper was published in volume 42 of the Proceedings of the Royal Society as 'Note on induction coils or "transformers"'.

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Ink and graphite pencil on paper
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10 pages

Creator name

John Hopkinson

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John Hopkinson, Paper, 'Note on induction coils or "transformers"' by John Hopkinson, 1887, PP/10/19, The Royal Society Archives, London,, accessed on 15 June 2024

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  • Proceedings Papers

    Dates: 1882 - 1894

    The archival collection known as 'Proceedings Papers' is comprised of manuscripts and occasional proofs of scientific papers sent to the Royal Society which were read before meetings of Fellows and printed in full in the Proceedings of the Royal Society.

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