1
R
6R
2
m1=16m
m2=8m
.
m3
4R. 6R
2R
4R
m3=21m 2
R m2
R m1
1
. t0=0
F . :
.
.
.
t
2.
.
t.
.
0-t.
1
.
F
0-t.
1
.
t.
1
.
t.
1
R2/2.
: m=1kg, R=1m, F=60N
.
u
1
u
,
1R
.1
.1R
.1
.1R
.
1R
.1
,
u
.1
1
1
u
.1
u
.1
.1
1
, u
u
u
1R
.1
u
: 2u
.1
.1
.1
2
u
u
,
.1
F T1 T2
21m
R
1R
.1
2R
: u
2
1
.1R
u . 2
.1
R
.2
u , 2
.2
.2
2
2R
.
(1) T2
T1
F
1
2 1 T1R T3 R 16mR 2 2 2R (2) (3): 1 6m
.2
.2
T1 T3
4m
T4
8m
2
(5)
T4
(4)
T2 R T4 R
.1
.1
(3)
2
T2
T1
T2
(2)
T1 T3 16m
1 8mR 2 2 2R
T2
T4
1
2m
(6)
T3
(5)
(6):
(1), (4)
3m
2
(7): F 12 N 5
1
.
(7) F 2 m/s2. 30m F 6 N, 2 10
F 15
3
4 N,
4
F 30
2 N.
t
2,
x,
x = x + 2R.
1 t2 2 2
x x
x
2
t
1 2
2R
t
2s, x =2m, x
t
u
4m
4m / s .
2
x = 2x
, .
. u
u
.1
u 2
.2
2m / s ,
1
u 2R
2
2rad / s .
.
WF
F x
240 J,
48 J,
x
W1
24 J.
x
W2
1 1
1
,
WT1
48 J.
WT1
1
.
1
WT1
WT1
WT1
x
R
1
x
T1R
1
x
T x
2T x
48 J.
. .
3
1
.
WF
.
.
dK dt dL1 dt
WT1
100%
WF
100%
F u
1
48J 100% 20% . 240J
u
1
R T3 R
176 J/s
dL 2 dt
dK1 dt
1
8 N路s.
2
2u
.1
48 J/s.