(51.1)
(51.1) : , , . (51.1)
(51.2)
dU , dA , dQ . dU , dA dQ . (51.2).
(51.1) , , , . . ().
, D U =0. , ,
. . , ó , , ( ).
52.
, . , , , (. 78). , , d l,
S , S d l=dV . ,
(52.1)
, V 1 V 2, (52.1):
(52.2)
. (52.2) , .
, V. . 79. dV pdV, . . dV, . , V 1 V 2, , , p = f(V) V 1 V 2.
, . , . ( ), ( , ). .
53.
, , 1 1 :
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- (/( × )).
, , 1 1 :
(53.1)
n= m / .
- (/( × )).
m,
(53.2)
.
, .
(51.2) 1 (52.1) (53.1):
(53.3)
, (. (52.1)) :
(53.4)
. . V 1 1 . (50.1),
(53.5)
, (53.3)
, ( p, V, ) V (. (53.4)), pVm=RT (42.4) T (p =const),
(53.6)
(53.6) ; , V . , , . (53.5), (53.6)
(53.7)
p V :
(53.8)
(53.5) (53.7) , . - . , , . , .
(. 50), V = 7 / 2 R. V (. 80) , V : (50 ) V = 3 / 2 R, CV = 5 / 2 R ( 7/2 R) v= 7/2 R. , , , , .
. , ( , ). , , , ( ). , 5/2 R 7/2 R. ( ) ( ).
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54.
, , , .
(V =const). () , V , (. 81), 12 , 1 3 . , . .
53, (dQ= d U+dA) , , , :
(53.4),
(54.1)
(p =const). () , V , V. (. (52.2)) V 1 V 2
(54.2)
(. 82). (42.5) ,
(54.2)
(54.3)
R: T 2 T 1 =1 , 1 R=A, . . R 1 1 .
( (53.4))
, (54.3).
(T =const). 41, :
() , V (. . 60), , , .
(52.2) (42.5) :
=const :
(dQ= d U+dA) ,
. . , , :
(54.4)
, , , .
55. .
, (dQ= 0) . . , , , . ( ), . .
(dQ= d U+dA) ,
(55.1)
. . .
(52.1) (53.4), (55.1)
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(55.2)
(55.3)
(55.2) (55.3) .
, p/V=g (. (53.8)),
p 1 p 2 V 1 V 2, ,
1 2 ,
(55.4)
, .
, V p, (55.4)
:
(55.5)
(55.6)
(55.4) (55.6) . (. (53.8) (53.2))
(55.7)
( ). (Ne, He .), , i =3, g=1,67. (2, N2, 2 .) i= 5, g =1,4. g, (55.7), .
() , V (. 83). , (pVg = const) , (pV = const). , 1 3 , , .
, . (55.1)
V 1 V 2, T 1 T 2
(55.8)
, (55.5), (55.8)
.
, 12 ( , . 83), , . , , .
, , . V p, (d T=0) ¥, (dQ =0) . , , .
(C =const) :
(55.9)
=(їp)/(їV) . , =0, n = g, (55.9) ; = ¥, n = 1 ; = p, n =0 , =V, n =¥ . , .
56. ().
( ) , , , . (. 84). , , (1 2) (2 1) . ( 1a2V 2 V 1 1) (d V >0), ( 2b1V 1 V 2 2) (d V< 0 ). , , , , . A= > 0 ( ), (. 84, ), A= < 0 ( ), (. 84, ).
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, . , .
, , . (51.1)
(56.1)
. . , , . , ,
Q 1 , , Q 2 , .
(56.2)
, , , , , . , , .
. , , , ; , . (- , . .), . . : 1) ; 2) ; , . . . .
57. ,
1865 . . . Q, , , .
, , dQ/T. , , , :
(57.1)
(57.1), , , dQ/T , , . ,
(57.2)
, dQ/T, S.
(57.1) ,
(57.3)
, , , :
(57.4)
(57.3) (57.4) , , . (57.3) (57.4)
(57.5)
. . ( ), ( ).
1 2, , (57.2),
(57.6)
, . (57.6) . , .
(57.6), . Ta
(57.7)
. . D S 12 1 2 1 2.
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dQ = 0, D S = 0 , , S= const,. . . . (57.7) , (T 1= T 2)
(V 1 = V 2)
: , . , , ( ).
: . W , , , ( , W³ 1, . . ( £ 1!)).
(1872), :