Weekend Homework: Exploding Applesauce

Nov 19, 2010 by

In the spirit of last week’s Video Story Problem, I thought I’d put together a conceptual story problem as an example for science teachers. Every year I make and can my own applesauce. It’s something that I like to do for Christmas gifts, and because my family is fanatical about applesauce (we have two young kids, which helps). Last year, I had a bit of a mishap, in that one of the canning jars I was using decided to explode (well, the bottom was blown out), and I had a HUGE mess in the canner.

I took a bunch of video after the fact because I thought it would come in handy someday, and it turns out that today is that day 🙂 I included a few variables and data in the video problem, but like any real world investigation I didn’t provide all the clues and information. For instance, I gave a few temperatures of the items involved (the jar, the applesauce, and the water in the canner), but didn’t address the fact that there are other variables to consider like the glass jars you’re using, any air pockets trapped in the jar before canning, etc.

In a way, this isn’t so much a problem as it is an exercise in observation. There’s obviously something wrong here, and while some of the information needed to solve the problem is present, there’s a great deal missing. Perhaps this might be used to help students understand the importance of gathering as much information as possible, or at least to approach investigations from a scientific perspective; trying to focus on pertinent data, identify variables and whether or not they are necessary to control. Enjoy the video, and if you see any fundamental flaws in my delivery of the problem, please let me know so i can make it better!