Properties of liquied helium II near 0°K are discussed Thermodynamically on the basis of the general two-fluid theory. From the fact that the specific entropy is proportional to T
3 and the second sound velocity remains finite as the temperature approaches to 0°K, it is concluded that the concentration of normal liquid ξ is proportional to T
4 in the equibibrium and that the functional form of s (p, T, ξ) is (function of p) ×ξ
2/T
5. These conclusions and LANDAU's statistical pesult that ξ is 4/3 of specific internal energy divided by the square of first sound velocity give the pesult :
(second sound velocity) =1/√2× (first sound velocity)
at 0°K, in agreement with the experiments of ATKINS and OSBORNE and of ATKINS and CHASE.
抄録全体を表示