Understanding the effects of gravity on a gas

AI Thread Summary
In an insulated container on Earth, gravity causes pressure differences, with lower pressure at the top than at the bottom. The kinetic theory of gases suggests that molecules have a random distribution of velocities, leading to uniform average kinetic energy throughout the gas. Some participants argue that this uniformity means there is no significant temperature gradient, while others reference the concept of lapse rate to support the idea of a temperature difference due to altitude. The discussion highlights differing opinions on whether gravitational effects can create a heat gradient in a confined gas. Overall, the consensus leans towards the absence of a temperature gradient in this scenario.
striphe
Messages
125
Reaction score
1
If a gas is enclosed in an insulated container on earth, I understand that at the top of the container there will be less pressure than at the bottom due to gravity.

What I want to know is if the top is colder due to the effects of gravity. If reliable sources could provided it would be appreciated (I can't seem to find any).
 
Physics news on Phys.org
Can you go into it any more than just simply 'no' curl, as to why?
 
The kinetic theory of gases describes the atoms or molecules of a confined gas as having a random distribution of the x,y and z components of velocity, and they move in straight lines until they collide with the container walls and bounce off. That description leads to a mixing that would have the population of molecules in any region of the container having the same average kinetic energy as the molecules in any other region of the container.

To produce the difference in pressure between the top and bottom due to gravity, change the reference to motion in straight lines into a reference to motion in parabolas that are very nearly straight lines. This makes the density and pressure slightly less at the top. Whether that causes a slight temperature gradient, I don't remember.
 
Curl said:
Wrong. The answer is yes. First off, Wikipedia is not a reliable source, and secondly that wiki article doesn't say anything about the question being asked.

Lots of people go to the mountains in the summer to escape the heat. Think about that for a second.

Google the phrase "lapse rate".
 
Mikelepore, My own consideration of what occurs within the gas regarding a possible heat difference; that heat is related to the kinetic energy of the molecules that make up the gas, with that kinetic energy being converted to gravitational potential energy if a molecule moves against the force of gravity.

D H, Curl may have read my other thread, "the altitude hypothesis" which brings about a particular dilemma based on this. The thread eventually came to a halt when I asked about lapse rate.

The hypothesis has two parts and what i was expecting was that the latter part to be the shortcoming. The users that posted opted for the first part as being the problem. That being a heat gradient does not emerge in contained body of gas under gravitational force.
 
I think it's easist first to watch a short vidio clip I find these videos very relaxing to watch .. I got to thinking is this being done in the most efficient way? The sand has to be suspended in the water to move it to the outlet ... The faster the water , the more turbulance and the sand stays suspended, so it seems to me the rule of thumb is the hose be aimed towards the outlet at all times .. Many times the workers hit the sand directly which will greatly reduce the water...

Similar threads

Back
Top