V水=m水/p水=4kg/1.0*10^3kg/m^3=0.004m^3=4L
p水=pgh=1.0*10^3kg/m^3 *10N/kg *0.3m=3000Pa
p=F/S=50N/0.01m^2=5000Pa
v=m/p=4kg/1*1000kg/立方米=0.004立方米
p=pgh=1*1000kg/立方米*10n/kg*0.3m=3000Pa
p=f/s=50n/0.01平方米=5000Pa
V水=m水/ρ水=4kg/1.0*103kg/m3=0.004m3=4L
p水=ρgh=1.0*103kg/m3 *10N/kg *0.3m=3000Pa
p=F/S=50N/0.01m2=5000Pa