, . , .
, .
( ), .
¾ .
, . , .
. .
( ) , . . , .
F ( ) F . :
F = - k × x
, , . . , . , :
v = dx /dt,
F = - b× (dx /dt).
, . = d2x /dt2:
F + F = m× a.
, :
m + b + kx = 0 (1)
m
= w02,
= b,
:
+ 2b + w02x = 0. (2)
x =x(t) (2):
x = A0× e- bt × cos(wt + j); (3)
(. 1).
. 1
0 ( t = 0); e =2,718 ; b , -1; w , /; t ; j .
:
= 0-bt. (4)
:
, (5)
w0 , . . . ( b) w , :
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w0 £ b (6)
.
j x0 t=0:
x0=A0×cos(j) (7)
. 1 , j = 0. t, e , :
A (t)/A (t+t)=e (8)
. . , ebt=e.
:
bt = 1 (9)
n 1 , T . :
T = . (10)
2p, 1 2pn w, . .:
w = 2pn = . (11)
D, A(t) , , . .:
(12)
d , . .:
d = ln D. (13)
:
d = bT; b = (14)
,
(11) (14), (3) :
(15)
(. 2) , . . . .
1. 40-50 ( 0).
. 2
2. , . t : T = t/n., n=20.
3. w.
4. 0 (40-50) , , , , , , , . .
5. T, , tn = T× n, n .
6. = (t).
7. t (. . 1).
8. , (9).
9. , (14).
10. , .
11. b, w, d, T, v. j .
12.
e% = .
1. .
2. .
3. .
4. : , 0, w, j, , v, b, d, t, , .
5. bt = 1 dT = 1.
6. .
7. t .
1. . ., . ., . . . .: . , 1973. 8.1, 8.2, 8.5.
2. . ., . . : 2 . .1. .: . ., 1972. .24.
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3. . ., . .: . ., 1998.