A
B
C F
D 2
2
F mg
7 F A
F ( )
A B C D
8 abc a bc
PaPbPc
( )
A
B
C Pa<Pb=Pc
D Pa=Pb=Pc
9
A
B
C
D -
10 L=0.5m OA,A m=3.0kg , , O
, 2.0m/s,g 10m/s2, OA
A6.0N B6.0N C24N D24N
11 M m
