So,  I’ve hit you with the Entropy post, and I think most of you have an intuitive (not necessarily correct!) idea as to what temperature is.  Little did you know I would be mixing the two together in my cocktail of science.  Well, here goes.


So, as I mentioned earlier, your concept of temperature may not be fully accurate.  Simply put, in the classical-thermodynamic way of looking at things, temperature is the amount of caloric fluid an object contains (OK, not that classical).  What  really mean to say is that temperature in the 19th century way of looking at things is how much kinetic energy the average particle in the object has (how fast the atoms are bumping, jiggling and spinning in their degrees of freedom).

Entropy, meet Temperature

So, as I’m sure you could predict, that wasn’t the whole story.  In fact, it has a rather simple, but AMAZING relationship with entropy.  If you recall, entropy is simply information/uncertainty.  What might that have to do with temperature?  Temperature is the change in energy required to change the entropy!  It is the “energy efficiency” of the system’s ability to have its entropy change (higher temperature = more energy to change the entropy by a certain amount).  Wow!  This makes sense when you think about it (after all, as your energy in a system increases, degrees of freedom “fill up”, and higher energy modes become available). So, rather than asking for a cold drink on a hot day, why not ask for a relatively certain drink on a information-full day!