Over at Uncertain Principles, Chad frets about committing physics heresy via a reading of Goldilocks and the Three Bears to his young offspring.
The story may convey a useful moral message, but it's way off base on the physics.
After all, the Papa Bear, being the biggest, presumably has the largest bowl of porridge. Here, the story fits what we know about thermodynamics, as the largest bowl should take the longest time to cool, and thus should be the hottest at any time before the porridge bowls reach thermal equilibrium with their environment.
The description provided of the other two bowls, though, is not consistent with known physics. The Mama Bear, as the other adult, ought to have the second-largest bowl of porridge, which, in turn, ought to be the second-warmest bowl of porridge (assuming that equilibrium has not been reached). But the story says that this bowl is too cold! Meanwhile, the Baby Bear, who ought to have the smallest portion of porridge, has a bowl that is "just right," neither too not nor too cold. As the smallest bowl, though, the Baby Bear's porridge ought to be the coldest of the three (until equilibrium is reached, of course). There is no way for the bowls as described to have the temperatures described, while being consistent with the known laws of thermodynamics.
It's a hilarious post. To me anyway. For several reasons. One being I always was bothered about the porridge business as a child for essentially the same reason, though I wouldn't have called it physics back then, just common sense. Two, this part slayed me:
The only way that the story can make sense is if, for some reason, the Mama Bear has the smallest portion of porridge. In which case, this is a story with a very different moral than the original--it's a story about the oppression of the Mama Bear**, either because the patriarchy is forcing her to eat only the scraps left behind after her husband and child have had their fill, or because the unhealthy woodland media culture has saddled her with a negative body image, leading to an eating disorder.
Because when we were growing up, the joke in our household was that our mom would die if hot food ever touched her lips. She was always so busy rushing around making sure the food was on the table and that dad and we kids had everything we needed and had plenty to eat and she often went without to make sure we had enough and she would be jumping up from the table throughout the meal to get this or that...by the time she settled down to eat the rest of us were half done and her food was cold. Which she ate along with her "special pop" (that's soda to you, bub) which was Fresca, "the light diet soft drink", which of course was supposed to help her lose weight and fit into the unhealthy woodland media culture (it was western Pennsylvania, you know) body image norms for females.
Methinks the Goldilocks story has a basis in patriarchal truth! Perhaps rather than worrying about Goldilocks's physics, Chad should just read his daugher Feminist Fairy Tales.
Hmm, I guess I figured that Mama Bear's porridge was sitting closer to the open window so it cooled down faster. Or maybe Papa Bear's was served out of the pan last, so it had less time to cool down. There are plenty of ways that physics can still apply here (I just got back from teaching 6th graders to try to come up with various explanations for our science test results- if we didn't find bugs today, does that mean the river's polluted, or are there other explanations? If we found that pH and dissolved oxygen levels are good, does that mean the river's not polluted, or could there be something else we should look for?)
Interestingly this was a major plot point in the very interesting, and humorous detective novel "The Fourth Bear". In that book Mama Bear's cool porridge proved that another bear had been there, eaten Baby's and Papa's porridge, then added new from the pot, allowing Baby's to cool to optimal temperature, while Papa's, in a larger bowl, stayed warm.
I never thought about other explanations before, I must admit.
What I want to know is why Papa bear is never the one to get up early and make porridge for the family breakfast.
With 3 year olds in the house, we've recently had some lengthy discussions about the thermodynamics of porridge. One hypothesis is that Mama Bear's bowl is actually more plate shaped so it has a larger surface area than either Papa or Baby bear's bowls.
I thought Baby Bear would have had an unbreakable wooden bowl that insulated the porridge, whereas the adults used china.