An open tank contains brine to a depth of 2 m and a 3-m-layer of oil on top of the brine. Density of brine is 1,030 kg/m3 and the density of oil is 880 kg/m3. What is the gage pressure (kPa) at the bottom of the tank?

Gage pressure at the bottom of the tank = 46.1kP

Explanation:

Note that it is required to expressed the gage pressure, pressure at the free surface=0 gage

Pressure due to the oil layer = (3m) * ((800kg/m^3) (9.81m/s^2)) / 1000=25.9kpa

Pressure due to the brine layer = (2m) * ((1030kg/m^3) (9.81m/s^2)) / 1000=20.2ka

Therefore, the pressure at the bottom=25.9+20.2=46.1kP