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If you have a pressurized container of sufficient size, would there be a pressure gradient due to gravity? Pascal's law indicates the pressure is the same everywhere in the container. Let's specifically speak of gas pressure.

Just Aguy
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If you have a pressurized container of sufficient size, would there be a pressure gradient due to gravity?

There will always be a pressure gradient due to gravity. How significant it is, however, depends on what you mean by "sufficient size".

For example, for the first 1000 meters above sea level, the increase in atmospheric pressure due to gravity is 11.3 pascals per meter. Considering the atmospheric pressure at sea level is 101,325 pascals, for a cubic meter of air the difference in pressure between the top and bottom would be negligible.

For the gradient to be non trivial, you would need a very tall container.

Hope this helps.

Bob D
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    Does the room I am sitting in qualify as a "container?" The ambient pressure at the surface of my desk is approximately 98.83 kPa, or so-says the barometric sensor in my cell phone. Is that "pressurized?" When I move the phone from desktop to floor and back again, the pressure-vs-time plot very clearly shows a change in pressure of about 10 Pascals. "significant?" – Solomon Slow Oct 04 '19 at 13:42
  • @SolomonSlow 10 pascals sounds about right if the height of your desk is about a meter. Not sure what you mean by "significant" though. Is a difference of10 Pascals compared to the total pressure of 98,830 Pascals significant? You tell me. – Bob D Oct 04 '19 at 14:05
  • Indeed, one could take the Earth as a 'pressurized container' where clearly there is a pressure gradient. Now, the OP is primarily misapplying Pascal's "Law"... – Jon Custer Oct 04 '19 at 14:06