Gauge pressure- tpr science workbook physics passage 10 #5

[faith hopelove]

The question asked: what is the difference in pressure between points x and y? I know that x does not have a gauge pressure so the difference in pressure is the gauge pressure of point y. What I do not understand and I hope someone can explain to me is why in the solutions they use 0.3m as the depth rather than 0.6m. Is y not below x by 0.6m?

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[faith hopelove]

Any takers? I'm just questioning the depth they used.

 

[FistLength]

Is it because the solutions have different densities, you would use .6 if they are in equal solution. My guess.

 

[faith hopelove]

That's a good point thanks.

 

[dudewheresmymd]

Is it because the solutions have different densities, you would use .6 if they are in equal solution. My guess.

if so, shouldn't it be rho1*.3*10 +rho2*.3*10? Wouldn't you sum the gauge pressures if they are different mediums?

 

[brood910]

You should know that d in pgd stands for the distance from a certain point in the fluid to the interface between two fluids with different densities. Thus, d1 = d2 = 0.3.
p1g1d1 + p2g2d2 = (p1 + p2)gd,

Note that air is also a fluid with different density. That's why we say d in pgd is the distance between a point in the water and the surface of water (water open to air).

So, if you replace fluid 1 with more fluid 2, then yes, you use 0.6.

 

[dudewheresmymd]

brood you're killing it with the fluids

 

[brood910]

brood you're killing it with the fluids