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..03
..03
2006
531
22.21
12
/ ( 3 30 200 6 )
: ..
: ..
: . ..
.
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| 3 | ||
| 4 | ||
| 5 | ||
| 6 | ||
| . tp,n |
6 .
:
( 1 ) , 3. ( 4);
, ( 2);
3 , , ( );
.
, .
, , .
|
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, .., .., .., .., .., ..
1
.
: , . .
m u. : p = m × u W = 
. , h ( ), , W = m × g × h. W = W + W .
n , , , , , .. .
:
P = m u 1 + m u 2 + + m un = const.
n ( ) , ( ) (, , ):
W = W 1 + W 2 + + Wn = const.
.
(, ) : D W = A .
, , , , .
( 1) 2 M, .
1
1, u, 2 ( ). , 1 2 . 2 ( ), M + m u 2. :
m × u + M × u 1 = (M + m)× u 2, (1)
m × u + M × u 1 = (M + m)× u 2,
m × u + M × u 1 ;
(M + m)× u 2 ;
: u 1 =0, m×u =(M + m)× u 2, M >> m, m × u = M × u 2,
. (2)
, M + m , (2):
W = 
= 
. (3)
(3), ( M + m) a, 1 h ( 2), (3) ,
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W = (M + m) × g h .
W = W 
.
, 
.
:
. (4)
m M , (4) h. 1
h = DC 1 = OC 1 OD = OC 1 OC 2×cos a = l ×(1 cos a),
OC 1 = OC 2 = l . 1 cos a = 2sin2 a/2, h = l × 2sin2 a/2.
( a 4¸5), sin a/2 a/2
h = 2 l × (a/2)2. (5)
a , b. 1 
. (5) 
.
(4),
. (6)
