2013-2014
II ( ) ( )
1. . , , . , v1 = 120 /, , v2 = 30 /. , : ) , ? ) , ?
2. . , , . , . .
3. . . , V1 =17,75 3? 8900 /3, 1000 /3.
4. . , 1000, 100 , 150 -200, ? = 4,2*103 /(× 
), =2,1*103/(× ), 
=3,4*105 /, L =2,3*106/, =4*102/ 0.
II ( )
( )
1. . , , , , . ρ0 =1000 /3.
2. . , . . .
II
| 8 ( ) |
1. .
) ,  (1), S , a t .  (2),  (3). , t = t1 + t2 =  (4), v =  (5), v = 48 /.
) t1 = t2 =  (6). S1 =  (7), S2 =  (8). S= S1 + S2 =  (9), , v =  (10), v = 75 /.
: ) 48 /; ) 75 /.
:
1. (1) - 1 .
2. (2), (3) (4) - 2 .
3. v (5) - 2 .
4. (6) - 1 .
5. (7), (8), (9) - 2 .
6. v (10) - 1 .
7. - 1 .
- 10 .
|
 2. .
: F , , F F/ , , N N/ - .
:
1. - 7 .
2. 3 .
- 10 .
|
3. .
V, , , V2. V2=V-V1, m=ρ(V-V1), ρ . (1)
, ,
FA = ρgV, ρ . (2)
, :
P=FA ρg(V-V1)= ρgV. (3)
V:  . (4)
, V = 203.
V2 = 203-17,753=2,253.
, : m =0,02 = 20.
:
1. (1) --------2 .
2. (2) --------2 .
3. (3) --------4 .
4. ------2 .
----------10 .
|
4. .
:
Lm + mΔt = ccmcΔtc + λmc + cmΔt, (1)
Lm , , mΔt , , 1000 0, ccmcΔtc - , () -200 0, λmc - , , cmΔt, - , -200 0.
(1) :  (2).
, m≈30.
:
1. (1) --------6 .
2. (2) --------3 .
3. -----1 .
----------10 .
|
| 8 ( ) |
1. .
  .  , ( , )  (1).
 ,  (2)  :  (3).
|
2. .
, .
, , (. 2.2). , . .
. , . , (. 2.3).
P. 2.2
l1 l2 . ,
Mgl1 = mgl2, (1)
- , - , g - .
 (2)
:
1. 3 .
2. 2 .
3. (1) 2 .
4. (2) 1 .
5. 2 .
10 .
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