[The Ninth Blog] Thermodynamics.

Since finals ended, I haven’t really thought about school. At all. Even though it’s only been, like, five days since we’ve been in physics class, I’ve basically forgotten everything. Well, not everything, but quite a bit. I’m forgetful, what can I say? :] 

I baked some pumpkin muffins this weekend. For Christmas, one of our neighbors gave us a jar of pumpkin bread/muffin mix with raisins in it that I finally decided to use on Saturday. They actually turned out to be pretty good. And the process involved physics, so all the better, right?

From the very beginning, physics was at play: when I set the oven to 350°, heat was added to the system in order to bring it up to temperature. Such a process is isochoric, as the volume of the oven cannot be changed. According to the ideal gas law PV = nRT, as temperature rose, so too did pressure. Also occurring due to the added heat was an increase in the system’s entropy.

Once the oven had reached 350°, it was time to put in the muffins. Since heat readily flows from hot to cold, heat was transferred from the surrounding air to the muffins, causing them to undergo a temperature and phase change. At this point, the muffins were taking part in an isobaric process. As the temperature of the muffins increased, it caused them to rise as they baked, with temperature and volume varying but pressure constant. Once the muffins were brought up to the same temperature as the oven, they finished baking in an isothermal process. [I think...] The muffins dropped slightly in height (volume decreased) as they continued to cook, since pressure was increasing as the batter became more dense, completing its change from a liquid-like substance to a solid, and temperature was being held constant.

And voila! The result: delicious pumpkin-raisin muffins and a nice lesson in physics. :]