How to Crush a Can
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How to Crush a Can
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Download film (right-click)Demonstration , Drama , Physics , Secondary
How to crush a can using a Bunsen burner and a bowl of water
Director's Notes:
A group of students try different ways to crush a drink can. Funnily enough, concentrating really hard doesn’t work very well — but boiling some water in it then inverting it into a bath of cold water: that does work.
If repeating this experiment yourself, be extremely careful to avoid scalding from the steam or burning from the hot can itself. Safety specs, as worn here, are a good basic precaution, but also think about what happens if you accidentally drop the can.
As ever, schools should perform a risk assessment and ensure adequate levels of supervision before attempting the experiment.
SciCast Notes:
A classic experiment, this. It’s quite tricky to get right with a drinks can, as it cools down very rapidly so you don’t have long to get it upside-down into water. The deft flick of the wrist shown here is one way, though the ring-pull isn’t the most secure place to hold the can — if it had come off, the children at the end of the bench might have had a hot can containing boiling water sailing through the air at them.
Safety concerns aside, it’s a decent film, and the experiment itself is shown clearly.
— Jonathan.