Tag: forces and matter

Questions Related to forces and matter

A tank $5\ m$ high is half filled with water and then is filled to the top with oil of density $0.85\ g\ cm^{-3}$. The pressure at the bottom of the tank, due to these liquids, is

  1. $1.85\ g$

  2. $89.25\ g\ dyne\ cm^{-3}$

  3. $462.5\ g\ dyne\ cm^{-2}$

  4. $500\ g\ dyne\ cm^{-2}$


Correct Option: C
Explanation:

We know that the pressure increases as we go deep into a liquid. The relation is given by $\Delta P = \rho g\Delta h$


Given that the tank is half filled with water and half with oil.
Thus, $h _\textrm{oil} = 2.5\textrm{ m}$ and $h _\textrm{water} = 2.5\textrm{ m}$

Thus, pressure at the bottom of the tank is $\Delta P = \Delta P _\textrm{oil} + \Delta P _\textrm{water} = 0.85\times 250g + 1\times 250g=462.5g \textrm{ dyne cm}^{-2}$