Pressure as a function of depth

[elitespart]

1. There is a 16.8 m tall oil-filled barometer. The barometer column is 80.0% filled w/ oil when the column of a mercury barometer has a height of 722mm Hg. If the density of mercury is 1.36 x 10^4 kg/m^3, what is the density of oil?

Homework Equations

P=Po + pgh
D=m/v

The Attempt at a Solution

so the oil barometer has 13.44 m of oil. I know density of the mercury and the height of the mercury barometer. Do i have to set abs. pressure of oil to that of mercury and go from there? Any feedback would be appreciated.

 

[denverdoc]

Is there a picture that goes along with this problem? Its worded in a way that confuses me (and you too, no doubt)?

Assuming the most straightforward situation,

Pa+Xrho*g*h=Pa+Hgrho*g*h. the Pa for ambient or atmospheric pressure cancel. G divides out. Does that help?

 

[elitespart]

yeah it is worded a bit weird. Ok, so what's Xrho and Hgrho. Do u mean the density of the oil and mercury by that? And also for the depth of the oil, do i use 16.8 or 13.44 which is the height of the oil in the barometer?

 

[denverdoc]

yep I should bite the bullet and download Latex, but yes rho(density) for oil and Hg. And assuming these are separate physical systems, the height for oil would be 13.44

 

[elitespart]

thx bro appreciate it.

 

[denverdoc]

No prob, keep coming back ;-D