# Talk:OpenStax University Physics/V2

## Errata in Volume 2 chapter summaries

Seems OK

### The Kinetic Theory of Gases

1. Not-to-worry I make this mistake during lecture all the time: ${\displaystyle {\bar {v}}={\sqrt {{\tfrac {8}{\pi }}{\tfrac {RT}{M}}}}}$ is the average speed, not the average velocity --Guy vandegrift (discusscontribs) 01:54, 2 February 2018 (UTC)

Seems OK

### The Second Law of Thermodynamics

1. "${\displaystyle \oint {\tfrac {dQ}{T}}}$ for any COMPLETE cyclic process." ... What is an INCOMPLETE cyclic process? (... or maybe this is something I should know about?)
2. "${\displaystyle \Delta S\geq 0}$ describes the change of entropy of a closed system under any REVERSIBLE process" Why must it be reversible?... (or maybe there is a way to decrease entropy in a closed system if the process is irreversible???)

## Where should I put all these equation sheets?

I am moving this discussion to Talk:OpenStax equations--Guy vandegrift (discusscontribs) 20:32, 28 February 2018 (UTC)