Fluid Dynamics Pressure Difference

[SNOOTCHIEBOOCHEE]

if you are given that a pressure displaces an oil (density = .85g/cc) 25mm in a contraption that looks like a long u shaped test tube, how would you find the realitve pressure difference?

 

[OlderDan]

if you are given that a pressure displaces an oil (density = .85g/cc) 25mm in a contraption that looks like a long u shaped test tube, how would you find the realitve pressure difference?

I'd probably try to figure out the weight of the on the high side that was higher then the oil on the low side, and divide that by the area of the base of the column of oil

 

[kyle8921]

To find the relative pressure difference, we need to use the equation for pressure, which is P = F/A, where P is the pressure, F is the force, and A is the area. In this case, the force is the weight of the displaced oil and the area is the cross-sectional area of the test tube.

First, we need to calculate the weight of the displaced oil. We can do this by multiplying the density of the oil (0.85 g/cc) by the volume of the displaced oil, which is the cross-sectional area (A) multiplied by the height (25 mm). This gives us the weight of the displaced oil in grams.

Next, we need to calculate the area of the cross-section of the test tube. This can be done by measuring the diameter of the test tube and using the formula for the area of a circle (A = πr^2).

Once we have the weight of the displaced oil and the area of the cross-section of the test tube, we can plug these values into the equation for pressure. This will give us the pressure exerted by the displaced oil in units of grams per square millimeter (g/mm^2).

To find the relative pressure difference, we need to compare this pressure to the pressure of the surrounding environment. This can be done by measuring the pressure of the surrounding air using a pressure gauge or by assuming a standard pressure of 1 atmosphere (101,325 Pa).

The relative pressure difference can then be calculated by subtracting the pressure of the surrounding environment from the pressure exerted by the displaced oil. This will give us the net pressure difference in units of grams per square millimeter (g/mm^2).

In summary, to find the relative pressure difference in this scenario, we need to calculate the weight of the displaced oil, the area of the cross-section of the test tube, and the pressure of the surrounding environment. We can then use these values to calculate the net pressure difference.