Saturday, September 29, 2007

Work, Heat Capacity and Reversibility

In Lecture 6 we fleshed out the ideas of work and heat a little more, showing how to take an infinitesimal quantity like dw and turn it into a macroscopic, measurable value. In the process, we distinguished between external and internal pressure, developed the heat capacity parameter and reminded ourselves that both heat and work are path functions.

Then we calculated general expressions for the work performed in two processes: free expansion into a vacuum and compression/expansion against constant external pressure, both irreversible processes. After defining reversibility, we addressed a third process: reversible, isothermal compression/expansion of a gas.

Quiz 1 on Monday. Any questions?

3 comments:

Anonymous said...

Should we bring a calculator?

rod said...

Yes, definitely.

rod said...

I bet the 10 second interval between the previous two comments fooled nobody.