Question

An open tank contain oil of specific gravity 0.75 on top of

water. If the depth of oil is 2m and the depth of water is 3m.
calculate the gauge and absolute pressures at the bottom of the
tank when the atmospheric pressure is 1bar

Answer 1

Let's not take into account atmospheric pressure.

Pressure P = Pressure of oil column + Pressure of water column

= h1 . d1.g + h2.d2. g

=( 0.5 x 800 x 9.8) + ( 1x 1000x 9.8) = 3920+ 9800 = 13720

Hence guage pressure at bottom is

P= 13720 N/ m^2