Full Text
A New Determination of the Charge of the Electron and of the Constants Associated with It.
(R. A. Millikan. A re-determination of the value of the electron and of related constants. Proceed. of the National Academy of Sciences. Washington. Vol. 3. Num. 4. p. 231—1917).
Beginning in 1913, Millikan carried out investigations of the charge of the electron \(e\), in connection with the works of Ehrenhaft that had appeared shortly before, which asserted that charges smaller than the charge of the electron were possible. The disagreement of the value of \(e\) obtained by Millikan with that usually used in calculations compelled him to broaden the experiment; finally, the connection of \(e\) with many physical constants brought out the full importance of this question, and in the present article Millikan describes the method that he used in his new determinations of \(e\), and which is identical with that which he had earlier used for determinations of \(e\).
The numerical values found by Millikan are the following:
| Charge of the electron | \(e = 4.774 \pm 0.005 \times 10^{-10}\) |
| Avogadro constant (number of gram-molecules in a gram) | \(N = 6.062 \pm 0.006 \times 10^{23}\) |
| Number of gas molecules in a cubic cm at \(0^\circ\) and 76 cm pressure | \(n = 2.705 \pm 0.003 \times 10^{19}\) |
| Kinetic energy of the translational motion of a molecule at \(0^\circ\) C | \(E_0 = 5.621 \pm 0.006 \times 10^{-14}\) |
| Change in the energy of translational molecular motion per \(1^\circ\) Celsius | \(E = 2.058 \pm 0.002 \times 10^{-16}\) |
| Mass of the hydrogen atom | \(m = 1.662 \pm 0.002 \times 10^{-24}\) |
| Planck’s element of action | \(h = 6.547 \pm 0.013 \times 10^{-27}\) |
| Wien’s constant of spectral radiation | \(C = 1.4312 \pm 0.0036\) |
| Stefan-Boltzmann constant of radiation | \(\sigma = 5.72 \pm 0.034 \times 10^{-12}\) (Watt cm\(^{-2}\). deg.\(^{-4}\)). |
I. Lazarev.