CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > General Forums > Main CFD Forum

entropy!!!!!!1

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   August 9, 2000, 05:19
Default entropy!!!!!!1
  #1
ram
Guest
 
Posts: n/a
hi.. why does anyone explain that the entropy appears to be a abstract concept compared to other calculabe quantities like energy, work and other measurable quantites like temperautre , pressure ?

thanks

ram
  Reply With Quote

Old   August 9, 2000, 06:32
Default Re: entropy!!!!!!1
  #2
mehdi ben elhadj
Guest
 
Posts: n/a
Hi,

Entropy can be defined as the measure of dissorder a system contains. One way to calculate entropy is to use a formula Ludwig Boltzman came up with:

S = k ln W

Where k is Boltzman's constant : k = 1.381 * 10-23 J/K

W represents the number of different ways in which energy of a system can be rearranged.

So, it's clear that entropy isn't "A Result" compared to other calculabe quantities like energy, work and other measurable quantites like temperautre .
  Reply With Quote

Old   August 10, 2000, 04:33
Default Re: entropy!!!!!!1
  #3
ram
Guest
 
Posts: n/a
Thank you..but i have one more thing . why does entropy appear to be a ABSTRACT concept compared to other comcepts ?

Regards

Ram
  Reply With Quote

Old   August 10, 2000, 18:08
Default Re: entropy!!!!!!1
  #4
clifford bradford
Guest
 
Posts: n/a
i think you've made the point. most properties of substances can be directly measured (or at least appreciated) in many cases by one of our five senses. Entropy is sensibly non-evident and can't be measured by any device. even quantities like magnetic field can be detected by various devices and visualized by iron filings etc. but entropy can only be calculated and it is one of the few quantities that has this characteristic. moreover it is tricky to pin down the entropy state of substance: we can often make accurate statements regarding it like hot air has a higher entropy than cold air at the same pressure but in general it's not necessarily easy to make such comparisons.
  Reply With Quote

Old   August 12, 2000, 07:48
Default Re: entropy!!!!!!1
  #5
ram
Guest
 
Posts: n/a
thank you for the clarification..

ram
  Reply With Quote

Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On



All times are GMT -4. The time now is 23:37.