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Hopkinson writes: 'According to the accepted theory of the alternate current dynamo, the equation of electric current in the armature is γy + Ry = periodic function of t, where γ is a constant coefficient of self-induction. This equation is not strictly true, inasmuch as γ is riot in general constant, but it is a most useful approximation. My present purpose is to indicate how the values of γ and of the periodic function representing the electromotive force can be calculated in a machine of given configuration.'

Annotations in pencil and ink throughout. Includes one diagram of Hopkinson's proposed dynamo.

Subject: Physics / Electricity

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 the theory of the alternate current dynamo'.

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Ink and graphite pencil on paper
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6 pages

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John Hopkinson

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John Hopkinson, Paper, 'Note on the theory of the alternate current dynamo' by John Hopkinson, 1887, PP/10/20, 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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