Understanding Pressure and Energy: Exploring the Differences and Examples

[Hypo]

Hallo everyone!

Im new here on this forum and I had a few questions in mind I would like to share them with everyone to get a perfect understanding with what I'm dealing with.

Now what is Pressure exactly? Is it a force or energy? I am kinda confused about it...?

For example the pressure from a compressed air tank blowing out through a small spot is that energy or force coming out?

Another example a balloon having a very very small poked whole to it... The air coming out from the pressure is that energy or force?

Thank you everyone :)

 

[Drakkith]

Energy is the ability for one system to perform work on another system. A compressed gas or a balloon has the ability to perform work on the gas outside by releasing it's own compressed gas. The gas has lots of kinetic energy as it exits the tank/balloon thanks to pressure generated by the compression inside the tank, or the squeezing by the balloon. So to answer your question, it is neither energy nor force coming out of the tank or balloon, it is gas molecules that are in motion which have energy and exert a force on other molecules.

The definition of pressure itself is the force per unit area applied in a direction perpendicular to the surface of an object. Gauge pressure is the pressure relative to the local atmospheric or ambient pressure.

 

[haruspex]

Consider a second balloon, twice the size of the first, same pressure. It has twice the potential to do work (energy), but the same pressure, so they're different things.

Consider a vessel of compressed gas with a bung in the top. A wide bung would be hard to keep in because its area is larger. Force = pressure times area.

 

[256bits]

Pressure is energy density.
See
http://hyperphysics.phy-astr.gsu.edu/hbase/press.html
where it is explained in regards to the Bernouili equation

 

[PJC01]

Hello and welcome to the forum!

Pressure is a measure of the force applied per unit area. It is not a force or energy in itself, but rather a way to quantify the force being exerted on a surface. For example, if you push down on a small area, the pressure will be higher than if you push down on a larger area with the same force.

In the case of the compressed air tank blowing out through a small spot, the pressure inside the tank is higher than the pressure outside, causing the air to rush out with force. This force is due to the high pressure inside the tank, but the pressure itself is not a force.

Similarly, in the case of the balloon with a small hole, the air escaping is due to the higher pressure inside the balloon compared to the lower pressure outside. Again, the pressure is not the force itself, but rather a measure of the force being exerted.

I hope this helps clarify the difference between pressure and force/energy. Let me know if you have any other questions and I'll be happy to help!