Calculating Air Column Height in a Glass Pipe with Water (105 kPa Pressure)

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Water in a glass pipe (pressure and volume)

Hi,
I have the following problem:we have a 1 meter long, thin glass pipe. It is open on both sides, we put that pipe 0,5 meters into a container filled with water. After that, we close the upper end which stucks out of the water, now we turn that pipe 180° around a horizontal axis, the air pressure is 105 kPa. Now I have to ascertain the height of the air column in the pipe.

I have the following ideas: first when we put the pipe into the water we have to add to the 0,5 meter the capillary force, I have an equation for that, but unfortunately I need the radius to calculate that. I guess I have to eliminate it somehow.
Now I have that water and when I turn the pipe arround I have to add the pressure of the water in the pipe (which is density of water*heigt*g) and the air pressure.
My suspicion is that the air in the pipe is pressed together a little bit because of that pressure. And that's all to it I imagine. But I have problems during calculation, because I can't get the radius out of my equations.

So I hope that anybody can help me, but PLEASE don't calculate anything in your answer (as far as possible) just give me a hint, because I want to solve it by myself (maybe later on I ask you to calculate something, but only if I'm completely exhausted Wink )
thanks
 
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Does really nobody has an idea ?
 
To solve this, I first used the units to work out that a= m* a/m, i.e. t=z/λ. This would allow you to determine the time duration within an interval section by section and then add this to the previous ones to obtain the age of the respective layer. However, this would require a constant thickness per year for each interval. However, since this is most likely not the case, my next consideration was that the age must be the integral of a 1/λ(z) function, which I cannot model.
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