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PONTIFICIAE ACADEMIAE SCIENTIARVM SCRIPTA VARIA - 28

(251-13) Teo=Y(i=p)= ©, CC
(251-14) |Y,=Y(i=p)=0 /(1+p 0

Pa

Re _ CA €
(251-15) [2

G,
©,

| i, _— {[x+(i-p)0,]e >"
Ra

5 : 1% 1;
(251-16) — = i e ©
R, L® i

(re i)e %‘1f
R ° |
M

= R, | ko 5 R, ]"
(251-17) R_, =a(t)] == |e R,= a(t) Ze
e® eO,

In these formulae, Ra, Re, R, Rg, R, i and p are functions
of time. The quantities (?- p), Yo, Y, ©, 0, Re/Row, R/Ru
are invariant.

Those formulae in which (0) and Ô appear involve the
supplementary hypothesis that à and o are constants (!). In the
same way the expressions (251-17) given for Rey and Ry are
valid only on this hypothesis (2).
It can thus be seen that in the exponential hypothesis, the
significant expressions depend on only two coefficients: the
coefficient of homogeneity k, and the time constant ©,.
Of all these relations, perhaps the most striking is that
which specifies that the ratio C/R, is a constant and equal to

() $ 230 to 232. _
() Relations (233-2), (233-3), (228-4) and (250-5) for Rom: relations
(229-5), (251-1) and first relation (251-17) for Ray .

‘11] Allais - pag. 108