Register to reply

Do not understand Helmholtz free energy

by annms
Tags: energy, free, helmholtz
Share this thread:
annms
#1
Apr16-12, 03:04 AM
P: 17
I'm currently learning thermodynamics from Schroeder's "An Intoduction to Thermal Physics".

He explains that in an environment of constant temperature, the system can extract heat from the environment for free when we create a system, and the Helmholtz free energy is that additional work needed that the heat did not cover.

My first point of confusion- why is it certain that heat flow from the environment to the system?
When we annihilate the system, why must there be heat transferred to the environment? Why not the other way around?

Secondly, why is it required that the environment is at constant temperature?

Lastly, why is the work done to make room for the system not accounted for? In most cases, you're creating a system that has some finite volume, so there should be a PV term. Since this is not accounted for here, what makes the Helmholtz free energy a useful quantity?
Phys.Org News Partner Physics news on Phys.org
Engineers develop new sensor to detect tiny individual nanoparticles
Tiny particles have big potential in debate over nuclear proliferation
Ray tracing and beyond

Register to reply

Related Discussions
Helmholtz free energy Introductory Physics Homework 5
Helmholtz free energy Classical Physics 0
Helmholtz free energy Advanced Physics Homework 10
Helmholtz Free Energy Advanced Physics Homework 0
Helmholtz free energy Classical Physics 3