why didn't water entere the bottle?

scientifico

Hi,

I put an overturned bottle inside a container filled with 0.5 m of water but water didn't enter inside the bottle.
Pressure acting out the bottle when is immersed is air pressure plus water pressure at its height and pressure inside bottle is just air so why didn't water entered the bottle ? Is it about gravity ?

Thank you

Low-Q

Air is compressible. Some water will enter the bottle, but not more than the water pressure allows with respect to the pressure and volume inside the bottle. 0.5m down in the water the pressure is only 1.049 bar, and the air above waterlevel is 1 bar. A difference of only 4.9%. However, you should see that some water enter the bottle.

Water pressure is a function of its mass and gravity. The deeper you go, the more mass are above you, the higher the pressure. If you submerge the bottle deep enough the pressure will fill the bottle with water almost completely. But still there is the same mass of air inside - just compressed into a very small space.

scientifico

So doesn't enter much water at 0.5 m because water compress air increasing its pressure ?

jbriggs444

Not much water enters because 0.5 meters worth of pressure does not compress the air very much.