jderulo said:
Let's check. If that's the pressure at the level of the dotted line, what is the pressure at the bottom of the tank? And also, based on your result, what is the pressure at the top of the left column of fluid?jderulo said:
jderulo said:
Are you aware that pressure is continuous across the interface between the air in the head space and the liquid immediately below?jderulo said:
Chestermiller said:
At what location(s) do you think your calculated pressure of 58680N.m^-2 is found?jderulo said:
No. That is not the pressure at the bottom of the tank.jderulo said:
I told you to forget about the tank, and to focus on the column of liquid on the left. The ideal gas law will not be part of the solution to this problem. Looking at the column of liquid on the left in your figure, did you notice that little triangular "symbol thingie" at the very top of the left column. The left column is full of liquid all the way up to that triangular "symbol thingie." Above that point there is air at atmospheric pressure, but below that point there is liquid. Were you aware of that?
Chestermiller said:
No. You went downward 6.7 m from the top water surface in the column. This puts you at the bottom of the tank. Now you've got to go back up 1.7 m to get to the water surface in the tank.jderulo said:
Chestermiller said:
No. If you go back upwards, you have got to subtract, not add.jderulo said:
Chestermiller said:
Yes. That's the air pressure in the tank headspace (over and above atmospheric pressure).jderulo said:
Why do you think they put the y into the problem description?jderulo said:
Not really sure can only assume it would make the solution glaringly obvious if it wasn't there...?Chestermiller said:
Exactly.jderulo said:
The formula for calculating air pressure in a tank with fluid level and height is P = ρgh, where P is pressure, ρ is the density of the fluid, g is the acceleration due to gravity, and h is the height of the fluid column. This formula assumes that the tank is open to the atmosphere and that there is no air inside the tank.
Yes, you can calculate air pressure in a closed tank using the ideal gas law, which states that PV = nRT, where P is pressure, V is volume, n is the number of moles of gas, R is the gas constant, and T is the temperature. You will need to know the volume of the tank, the number of moles of air inside the tank, and the temperature of the air.
The fluid level and height directly affect the air pressure in a tank. As the fluid level increases, the height of the fluid column also increases, resulting in an increase in air pressure. Conversely, as the fluid level decreases, the height of the fluid column decreases, resulting in a decrease in air pressure.
The most common units used to measure air pressure in a tank with fluid level and height are pounds per square inch (psi) or kilopascals (kPa). However, other units such as atmospheres (atm) or millimeters of mercury (mmHg) may also be used.
Yes, the air pressure in a tank with fluid level and height can change over time. This can be due to a variety of factors such as changes in temperature, changes in the fluid level, or changes in the amount of air inside the tank. It is important to regularly monitor and adjust the air pressure in a tank to ensure safe and efficient operation.