Physical ReviewAmerican Physical Society, 1913 In Feb. 1903, the separate publication of the Bulletin of the American Physical Society was discontinued and Its Proceedings published in the Physical review. |
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amperes anode apparatus bolometer brass bulb Bureau of Standards carbon cathode cent circuit coefficient coil College column constant copper correction curve cylinder decrease determined diameter disc discharge current distance drop effect electrical electrometer electrons emission energy equation error experimental experiments filament film formula galvanometer gases given glass heating hydrogen increase Instructor in Physics insulation lamp liquid air magnetic field manometer Mass maximum means measured mercury metal method molybdenite nitrogen observations obtained ohms oxid oxygen Phil Phys plate platinum Poiseuille's law positive ions potential difference Professor of Physics rays reflection refractive index resistance Röntgen rotations saturation current selenium shown shows space charge spark gap specimen spectrum stibnite surface Table temperature theory thermionic current tube tungsten Univ University V₁ vacuum vapor pressure velocity Volta effect voltage volts wave-lengths wire Young's modulus
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Página 402 - Abstract of a paper presented at the New York meeting of the Physical Society, October 18, 1913.
Página 139 - These results illustrate very clearly the sort of consistency obtained in these observations. The largest departure from the mean value found anywhere in the table amounts to 0.5 per cent and "the probable error" of the final mean value computed in the usual way is 16 in 61,000. Instead, however, of using this final mean value as the most reliable evaluation of e, it was thought preferable to make a considerable number of observations at atmospheric pressure on drops small enough to make...
Página 77 - Abstract of a paper presented at the Washington meeting of the Physical Society, April 25 and 26, 1913, 1 "A Micropyrometer,
Página 407 - An examination of some of the heating curves will perhaps give the incorrect impression that Ac2 is an evolution rather than an absorption of heat. The swing back at the maximum is very abrupt, following what appears to be a gradual building up of this maximum from an indeterminate low temperature.
Página 414 - ... not more than a few hundredths of a micron. The cathode consists of a body which can be electrically heated (such as a tungsten or tantalum filament) and, suitably located with reference to this portion, an electrically conducting ring or cylinder, consisting preferably of molybdenum or tungsten or other refractory metal. The ring or cylinder is connected either to the heated portion of the cathode, or to an external source of current by means of which its potential may be brought to any desired...
Página 406 - ... is attained and narrow enough that the contour of the curves is not distorted; we have found a 2° interval satisfactory. 5. The sensibility of the apparatus indicating temperatures and differences of temperature should be of the order of 0.01° and time should be measured to better than 0.2 second. Among the results of this investigation may be mentioned the demonstration that the inverse rate and differential methods, the latter plotted as the derived differential curve, give identical results...
Página 457 - Concerning this point, the attention of the writer has been called to the fact that probably much less than one percent of this contact has ever been seen and examined.
Página 406 - Small samples (i g. or so) give sharper results than large samples. 4. The interval of recording temperatures should be wide enough that sufficient sensibility is attained and narrow enough that the contour of the curves is not distorted; we have found a 2° interval satisfactory. 5. The sensibility of the apparatus indicating temperatures and differences of temperature should be of the order of 0.01° and time should be measured to better than 0.2 second.
Página 423 - If the temperature of the filament is low, only a small number of electrons escape from it and, consequently, only a small discharge current (the saturation current) can be sent through the tube. Increasing the impressed voltage above that needed for this current value causes no further increase in current. It simply increases the velocity of the cathode rays and hence the penetrating power of the Rontgen rays.
Página 117 - The substitution in this equation of an approximately correct value of e yields a with an error but one third as great as that contained in the assumed value of e.