T = 115 + 460 = 575 degrees.
53.33 × 575
Hence v = ----------- = 2.84 cubic feet, and
10,800
1 1
Weight per cubic foot = - = ---- = 0.352 pounds.
v 2.84
Table 27 gives the weights and volumes of air under atmospheric pressure
at varying temperatures.
Formula (9) holds good for other gases with the change in the value of
the constant as follows:
For oxygen 48.24, nitrogen 54.97, hydrogen 765.71.
The specific heat of air at constant pressure varies with its
temperature. A number of determinations of this value have been made and
certain of those ordinarily accepted as most authentic are given in
Table 28.