Question

A tank $2m$ high is half filled with water and then filled to the top with oil of density $0.80g/cc$. What is the pressure at the bottom of the tank due to these liquids (Take $g=10m{s}^{-2}$) is

• A. $1.80\times {10}^{3}N{m}^{-2}$
• B. $0.9\times {10}^{3}N{m}^{-2}$
• C. $1.8\times {10}^{4}N{m}^{-2}$
• D. $0.9\times {10}^{4}N{m}^{-2}$

Answer 1

Answer: (C)

$1.8\times {10}^{4}N{m}^{-2}$

Density of oil=0.80 g/cc=800 kg/m${}^3$

Density of water=1 g/cc=1000 kg/m${}^3$

Pressure of water=Height will be 1 m half filled

$⟹hdg=1m\times 1000kg/m^3\times 10m/s^2=10000Pa$

Pressure by oil$=hdg$

Total pressure$=(1\times 8000\times 10)=8000Pa+10000Pa=18000Pa=1.8\times {10}^{4}N/m^2$