(
)
(Law of Universal Gravitation)
A (1) (2)1687
(3)
(Gravitational force)
B
F
GMm R2
C R3 T2 GMm R2
F
m
2
4 T
K1
R
T GMm R2
F
2
F
2
R3 K1 m 4
2
R (
M
K1 ) m 4 R3 F
K2m R2
D (1) (2) (3)
(
( ) A (1) A
C D
(2)B B (3) ( (4)
A B (
) C D
)
)
K1 ) R2 K3M R2 2
(
K2m R2 F
GMm R2