Understanding Pressure in Liquids: The Role of Electromagnetic Forces

In summary, the pressure in liquids or gases is caused by the electromagnetic force between atoms and molecules. This force, known as Van der Waals force, accounts for the majority of the repulsion and outward pressure when molecules are forced together. However, it should be noted that in a gas or liquid, most atoms are neutral and do not have an electric charge, meaning that pressure cannot solely be attributed to electromagnetic origins. Further research is needed to understand how systems can have zero pressure.
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Delta2
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What causes the pressure in Liquids(or gases)? Is it deep down of electromagnetic nature? By that i don't mean that there are macroscopic electromagnetic fields from a liquid under pressure but at the microscopic level the pressure is caused by electromagnetic force between the atoms/molecules of the liquid and of the surrounding media.
 
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http://en.wikipedia.org/wiki/Van_der_Waals_force" [Broken] probably account for the majority of the repulsion (& thus outward pressure) when molecules are forced together.
 
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  • #3
Your question is quite interesting.

One direction to proceed to understand what systems have zero pressure?

Another point to note - apropos Jack's comment - is that most atoms in a gas/liquid are neutral. So it can't really be electromagnetic in origin. If you have a gas of neutrinos - which don't have any electric charge at all - they will still have pressure.

Hope this spurs you on a bit.
 

1. What is pressure in liquids and how is it measured?

Pressure in liquids refers to the force exerted by a liquid on a surface. It is typically measured in units of Pascals (Pa) or pounds per square inch (psi). Pressure can be measured using instruments such as a pressure gauge or a manometer.

2. How do electromagnetic forces play a role in understanding pressure in liquids?

Electromagnetic forces play a crucial role in understanding pressure in liquids. These forces are responsible for the interactions between charged particles in the liquid, which determine the behavior of the liquid under pressure. Without understanding these forces, it would be impossible to accurately predict the pressure in a liquid or how it will behave under different conditions.

3. What is the relationship between pressure and depth in liquids?

In liquids, pressure increases with depth due to the weight of the liquid above. This is known as hydrostatic pressure. The deeper you go in a liquid, the greater the pressure becomes. This relationship is described by the equation P = ρgh, where P is pressure, ρ is the density of the liquid, g is the acceleration due to gravity, and h is the depth.

4. How does temperature affect the pressure in liquids?

Temperature can affect the pressure in liquids in several ways. First, as temperature increases, the particles in the liquid gain more energy and move faster, resulting in increased pressure. Additionally, changes in temperature can also cause the liquid to expand or contract, which can lead to changes in pressure. This is known as thermal expansion.

5. How is pressure in liquids used in real-world applications?

Understanding pressure in liquids has many practical applications in various fields. For example, it is essential in designing hydraulic systems, such as in car brakes or heavy machinery. It is also crucial in the study of weather patterns, as changes in pressure can indicate the movement of air masses. Pressure in liquids is also utilized in medical devices, such as blood pressure monitors, to measure the pressure in the veins and arteries.

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