I had incorrectly assumed that this was a familiar parameter for everyone. It is also likely that it would take longer to reach thermal equilibrium because metal has a higher thermal conductivity than plastic. The engine p-v diagram question was the muddiest part. We will spend much more time with this concept as we proceed with the thermodynamics lectures, so if it was a little unclear at this stage that is okay. During this process the pressure and temperature of the gas increase and the specific volume decreases.
Energy is extracted to drive the compressor.
During this process the pressure and temperature decrease. I am a bit confused about the nature of energy conversion, I guess we'll get to that more later . Yes we will. Hang on for a few lectures. No, not necessarily.