instrument for measuring the temperature, whose the
action is based on dependent, to -.ti pressure or the volume of
perfect gas from the temperature. G. T. of the constant volume
(Fig.), which is the filled with gas balloon of 1 constant volume,
connected by thin tube 2 with device 3 for measuring the pressure, most frequently use.
In such a g. T. a change in the temperature of gas in the
balloon is proportional to a change in the pressure. G. T.
measure temperatures in the range from ~2K to 1300 K. predel'nos
obtainable accuracy g. T. depending on the measured temperature of
e*y0-3- 2*y0-2deg. G. T. of such
high accuracy- complex device; with the measurement by it of
temperature they consider: the deviation of the properties of
the gas, which fills instrument, from the properties of perfect gas;
change in the volume of balloon with a change in the
temperature; the presence in gas of the admixtures, which are
especially condensed; absorption and the desorption of gas by the walls of balloon; gas diffusion through the walls, and also
the temperature distribution will lengthwise connect, tubes.
The temperature scale g. T. coincides with the the
thermo-dynamic by the temperature scale, and g. T. adapts as primary
thermo-metalRICh of the instrument (see the
temperature scales). Temperatures of the fixed
points (datum points) of international practicaltemperature scale are determined with the aid of g.
T..
Lit.: Popov M. M., thermometry and
calorimetry, 2 publ., M., 1954.
