Classical Physics

On a New Physical Definition of Pressure in a Closed Space

Authors: Tai Choon Yoon
Comments: 5 Pages.

In physics, pressure is defined as p = F/A, where A is the cross-sectional area. According to the definition, in the kinetic theory of gases, the average translational kinetic energy is calculated as E_k =3/2 k_B T. If the definition of pressure is changed to P^' = 2F/S, the coupling coefficient 3/2 disappears, resulting the interacting kinetic energy E_i = k_B T. From this, we can derive the relation P^' V = E_i = Nk_B T of the ideal gas law. This can be applied to measure the temperature of the energy constituting the universe, i.e., T= E/k_B. Here, S represents the surface area, because there are three directions of interaction in a closed space. Since E_i is the interacting kinetic energy, the newly defined pressure (P^') is also the result of interaction, and has two forces: repulsive force and contractive force.
Category: Classical Physics