用一弹簧测力计称的一空瓶重1N,若在空瓶中装满水时称其总重3N,若在空瓶中装满另一种液体时称其总重2.5N,求: (1)空瓶的容积,(2)液体的密度.(g取10N/kg)

问题描述:

用一弹簧测力计称的一空瓶重1N,若在空瓶中装满水时称其总重3N,若在空瓶中装满另一种液体时称其总重2.5N,求:
(1)空瓶的容积,(2)液体的密度.(g取10N/kg)

(1)已知G=1N,G总1=3N,G总2=2.5N,
则G=G总1-G=3N-1N=2N,则m=

G
g
=
2N
10N/kg
=0.2kg;
V空瓶=V=
m
ρ
=
0.2kg
1.0×103kg/m3
=0.2×10-3m3
答:空瓶的容积是0.2×10-3m3
(2)G=G总2-G=2.5N-1N=1.5N,则m=
G
g
=
1.5N
10N/kg
=0.15kg;
V=V空瓶=0.2×10-3m3
ρ=
m
V
=
0.15kg
0.2×10−3m3
=0.75×103kg/m3
答:液体的密度是0.75×103kg/m3