swansont Posted August 31, 2004 Posted August 31, 2004 But I get ~10 m with every radius I'm testing with >0,0005, that can't be correct. Yeah, I'm not convinced that the equation is completely correct.
osram Posted August 31, 2004 Author Posted August 31, 2004 Yeah, I'm not convinced that the equation is completely correct. Which one? The one pulkit posted, or the one I made out of pulkits?
Primarygun Posted September 1, 2004 Posted September 1, 2004 After not sleeping for the whole night before the new school day, something reminds me. The diagram which is ugly drawn by me shows that when a vacuum machine extracts particles above a whole closed container which is with some water, will the water be extracted upwards? The answer is no, it's because water is not compressible( It doesn't vary itself very much due to the strong intermolecular forces). Maybe I should learn the kinetic theory before reading some gas law. I totally omitted something:) Now I got of something. What's the force by the surface of water acting downwards? 0 or others? I need you help.
Primarygun Posted September 1, 2004 Posted September 1, 2004 What's the force by the surface of water acting downwards? It's close to 0 .
osram Posted September 1, 2004 Author Posted September 1, 2004 The water starts boiling if it's low enough pressure in the vacuum-machine, doesn't it?
swansont Posted September 1, 2004 Posted September 1, 2004 Which one? The one pulkit posted, or the one I made out of pulkits? They were equivalent, weren't they? Anyway, surface tension isn't the whole story. Adhesion to the bottle matters as well.
Primarygun Posted September 2, 2004 Posted September 2, 2004 The water starts boiling if it's low enough pressure in the vacuum-machine, doesn't it? The rate is faster than at standard pressure. In my posted diagram, Is the force acting to left and right large than the force acting downwards? It is 1atm more in my case, right?
pulkit Posted September 2, 2004 Posted September 2, 2004 I should have stated that my formula also assumes that the angle of contact with the bottle is 0 degrees, whilst in reality this angle would be different for water and say glass (between 50 and 60 degrees). That would then account for adhesive and coersive forces too and add an extra cosine of theta factor along with h * rho * g.
Primarygun Posted September 3, 2004 Posted September 3, 2004 If the water in post 1 is not fully filled, and the space above the water of the bottle is vacuum, is that the pressure in h=1 acting towards horizontal(left and right) greater than the pressure acting downwards?
Primarygun Posted September 3, 2004 Posted September 3, 2004 Moreover, why do the pressure of the evaporated water is 1 atm when they turn into liquid again?
Primarygun Posted September 12, 2004 Posted September 12, 2004 It is really a old post but I want to get a bit more knowledge of it. The assumption is that the bottle is fully with water. If there is some air inside, is the job of us is to find out how many heights is displaced by the air,right?
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