Question

A pressure gage connected to a tank reads 55 kPa at a location where the atmospheric pressure is 72.1 cmHg. The density of mercury is 13,600 kg/m3 . Calculate the absolute pressure in the tank.

Answer 1

Step-by-step explanation:

Given

Gauge Pressure of a tank is

`P_(gauge)=55\ kPa`

at that place atmospheric Pressure is
`h=72.1\ cm\ of\ Hg`

Density of mercury
`\rho _(Hg)=13600\ kg/m^3`

Atmospheric Pressure in kPa is given by

`P_(atm)=\rho _(Hg)* g* h`

`P_(atm)=13600* 9.8* 0.721`

`P_(atm)=96.09\ kPa`

and Absolute Pressure is summation of gauge pressure and atmospheric Pressure

`P_(abs)=P_(gauge)+P_(atm)`

`P_(abs)=55+96.09=151.09\ kPa`