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What’s the Problem?: Air Cannon

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While the school year ramps up, I’ll try to post a couple things I’ve used in class in the past. In the upper Midwest (mostly), there’s a chain of sandwich shops called Erbert and Gerbert’s. In part because of how late they delivered, a lot of my limited-college-money was given to them, quite happily, in exchange for soup or submarine-themed-subs. The best part is that they pinch out the squishy middle part of the bread to make room for fillings, and give you the “guts” alongside your main meal. Now I’m hungry.


E&G is also known for their somewhat strange commercials. Besides having a pig as a mascot, their commercials were usually pretty (wonderfully) strange. Take this one, for example.

Act 1: Observations and Hook

I use this video during Newton’s Laws of Motion. It could also be used for some other mechanics-related topics.

Act 2: Questions, Possibilities, Resources

  • What the what??
  • Where do you see Newton’s Laws in the video?
  • Would the air cannon still work without the fog/smoke stuff?
  • If you make the shape of the output hole square, what will the vortex look like?
  • What does inertia have to do with how the smoke ring forms?
  • List basic parts (or draw a schematic) of air cannon parts.
  • How does the length of the barrel affect the speed of the vortex?
  • Why does the size of the vortex grow as it travels?
  • What would you change in the cannon to get a slower-moving ring?
  • How does air have enough force to knock things over?
  • What if you put confetti inside?

Act 3: Resolution and Continuation

  • It’s pretty easy to make your own air cannon. The second link actually has a number of answers for Act 2.
  • Propose your own air cannon design using a cardboard box and any other materials.
  • Would a similar-sized cardboard version of the video air cannon have the same power/speed/force?

In case you love this video as much as I do, here’s the behind the scenes video of how they made the air cannon (plus a flash of math, a quick conversation with a physicist, and some sandwiches).


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