Question

初三物理液体压强练习题

26和27题，26题的图在27题旁边 要过程，谢谢了

Answer 1

27.1V=0.4m×0.2m×0.1m=0.008m^3漂浮时，浮力和重力平衡ρ水V排g=ρ木VgV排=ρ木Vg/ρ水=0.008m^3×600Kg/m^3÷1000Kg/m^3=0.0048m^3V露=V-V排=0.008m^3-0.0048m^3=0.0032m^327.2最大V排'=V=0.008m^3木头原质量m木=ρ木V=600Kg/m^3×0.008m^3=4.8Kg漂浮时浮力等于重力F浮=ρ水V排'g=m总gm总=ρ水V排'=1000Kg/m^3×0.008m^3=8Kg剩下的木头质量m木'=m总-m货=8Kg-5.9Kg=2.1Kgm挖=4.8Kg-2.1Kg=2.7Kg=2700gV挖=m挖/ρ木=2700g/0.6g/cm^3=4500cm^326.1P水=ρ水gh=1000Kg/m^3×10N/Kg×0.1m=1000PaF水=P水S=1000Pa×20×10^(-4)m^2=2N26.2F=G水+G杯=3N+1N=4NP=F/S=4N÷[20×10^(-4)m^2]=2000Pa

Answer 2

（1）m木=p木V木==4.8kgG木=m木g=4.8kg=48NF浮=G木=48N由F浮=p液gV排得：V排=F浮/p水g=48N/=0.0048所以:V露=V木-V排=0.008-0.0048=0.0032

Answer 3

1.V木=0.4CM*0.2CM*0.1CM=0.008M3M木=PV=4.8KGF浮=G木=G小G=48NV液=F浮 /Pg=0.0048M3V露=V木-V液=0.0032M3