Energy density versus pressure?

Thread starter Sanev
Start date Nov 6, 2017
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Density Energy Energy density Pressure

AI Thread Summary

Energy density (U) can be related to pressure (p) through the equation U.Area = F, where force (F) is defined as pressure multiplied by area. The confusion arises in understanding when energy density can be equated to pressure. In certain contexts, such as in thermodynamics and fluid mechanics, energy density can indeed be interpreted as pressure, particularly when considering systems in equilibrium. The relationship holds true when analyzing the energy per unit volume in a system, where pressure reflects the energy density of the material. Clarifying these concepts is essential for a deeper understanding of their interrelation in physical systems.

Nov 6, 2017

Sanev

If i have Energy Density (U) -> U.Area= F but F.Area = pressure (p) but p must be U . I'm confused! In which cases we can say that energy density is pressure?

Last edited by a moderator: Nov 6, 2017

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Nov 6, 2017

A.T.

Science Advisor

Sanev said:

If i have Energy Density (U) -> U.Area= F but F.Area = pressure (p) but p must be U . I'm confused! In which cases we can say that energy density is pressure?

http://hyperphysics.phy-astr.gsu.edu/hbase/press.html

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