The discharge of electricity through gases : lectures delivered on the occasion of the sesquicentennial of Princeton University / by J.J. Thomson ; with diagrams.

  • Thomson, J. J. (Joseph John), 1856-1940.
Date:
1898
Catalogue details

Licence: Public Domain Mark

Credit: The discharge of electricity through gases : lectures delivered on the occasion of the sesquicentennial of Princeton University / by J.J. Thomson ; with diagrams. Source: Wellcome Collection.

Provider: This material has been provided by the Francis A. Countway Library of Medicine, through the Medical Heritage Library. The original may be consulted at the Francis A. Countway Library of Medicine, Harvard Medical School.

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    mv = tip. e From these we get, m_ OH*? e~2 W ' 2W v = QHP> relations which enable us to determine m \ e and v. The following are the results of an experiment of this kind. The cathode was slightly curved so as to focus the rays on the slit; the coil was turned on and quickly turned off again. The charge which entered the cylinder raised a capacity of 1.5 micro- farads to 16 volts. Hence, — Q = 1.5 X 10-15 x 16 X 10-8 . = 2.4 X lO6. The impact of the cathode rays on the thermo- electric junction was sufficient to produce in the thermo-electric circuit an electro-motive force of about 52 micro-volts. Taking 16 micro-volts as corresponding to a temperature difference of 1 degree, this means a rise in temperature of the junction of 3.37. The weight of the iron in the junction = .021 gr. copper in the junction = .03