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70
Ãëàâà òðåòüÿ
∑
=
∂
∂
⋅
∂
∂
+
∂
∂
⋅
∂
∂
+
∂
∂
⋅
∂
∂
=
n
j
i
j
r
j
i
j
r
j
i
j
r
j
jri
q
z
q
z
q
y
q
y
q
x
q
x
ma
1
, (3.1.7)*
nj ,...,2,1=
.
Òàêèì îáðàçîì ñ ïîìîùüþ ðàâåíñòâà (3.1.7)* ìû óáèðàåì ñóììè-
ðîâàíèå ïî j èç ðàâåíñòâà (3.1.7).
1
T
- îäíîðîäíàÿ ëèíåéíàÿ ôóíêöèÿ îò
q
&
:
∑∑ ∑
== =
=
∂
∂
∂
∂
⋅=
n
r
n
i
n
r
rri
r
i
r
r
qaq
t
x
q
x
mT
11 1
1
2
2
1
&&
, (3.1.8)
ãäå
∑
=
∂
∂
⋅
∂
∂
+
∂
∂
⋅
∂
∂
+
∂
∂
⋅
∂
∂
=
n
j
j
r
jj
r
jj
r
j
jr
t
z
q
z
t
y
q
y
t
x
q
x
ma
1
, (3.1.8)*
nj ,...,2,1=
.
0
T
ÿâëÿåòñÿ ôóíêöèåé îò
tqqq
n
,,..,,
21
:
∑
=
∂
∂
=
n
r
r
r
t
x
mT
1
2
0
2
1
. (3.1.9)
Äëÿ ñòàöèîíàðíûõ ñâÿçåé, òî åñòü ñâÿçåé, äëÿ êîòîðûõ
()
nrr
qqqxx
,...,,
21
=
è, ñëåäîâàòåëüíî,
0≡
∂
∂
t
x
r
, êèíåòè÷åñêàÿ ýíåðãèÿ
áóäåò îäíîðîäíîé ôóíêöèåé âòîðîé ñòåïåíè îòíîñèòåëüíî îáîáù¸ííûõ
ñêîðîñòåé, òî åñòü
∑∑
==
==
n
r
n
i
irri
qqaTT
11
2
2
1
&&
. (3.1.10)
Âåðí¸ìñÿ ñíîâà ê îñíîâíîìó óðàâíåíèþ (2.1.6)
()
∑
=
=δ−
N
r
rrr
xXxm
1
0
&&
. (2.1.6)
70 Ãëàâà òðåòüÿ
n
∂x j ∂x j ∂y j ∂y j ∂z j ∂z j
ari = ∑ m ∂q
j =1
j ⋅
r ∂qi
+ ⋅ + ⋅
∂qr ∂qi ∂qr ∂qi
, (3.1.7)*
j = 1,2,..., n .
Òàêèì îáðàçîì ñ ïîìîùüþ ðàâåíñòâà (3.1.7)* ìû óáèðàåì ñóììè-
ðîâàíèå ïî j èç ðàâåíñòâà (3.1.7).
T1 - îäíîðîäíàÿ ëèíåéíàÿ ôóíêöèÿ îò q& :
n n
∂x r ∂x r n
∑ m ⋅ 2∑ ∂q ∑ a q&
1
T1 = q& i = , (3.1.8)
i ∂t
r r r
2 r =1 i =1 r =1
ãäå
n
∂x j ∂x j ∂y j ∂y j ∂z j ∂z j
ar = ∑ m ∂q
j =1
j
r
⋅ + ⋅ + ⋅
∂t ∂qr ∂t ∂qr ∂t
, (3.1.8)*
j = 1,2,..., n .
T0 ÿâëÿåòñÿ ôóíêöèåé îò q1 , q2 ,.., qn , t :
2
∂x
n
∑
1
T0 = mr r . (3.1.9)
2 r =1 ∂t
Äëÿ ñòàöèîíàðíûõ ñâÿçåé, òî åñòü ñâÿçåé, äëÿ êîòîðûõ
∂x r
x r = x r (q1 , q2 ,..., qn ) è, ñëåäîâàòåëüíî, ≡ 0 , êèíåòè÷åñêàÿ ýíåðãèÿ
∂t
áóäåò îäíîðîäíîé ôóíêöèåé âòîðîé ñòåïåíè îòíîñèòåëüíî îáîáù¸ííûõ
ñêîðîñòåé, òî åñòü
n n
∑∑ a
1
T = T2 = & & .
ri q r qi (3.1.10)
2 r =1 i =1
Âåðí¸ìñÿ ñíîâà ê îñíîâíîìó óðàâíåíèþ (2.1.6)
N
∑ (mx&&
r =1
r − X r )δx r = 0 . (2.1.6)
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