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Thursday, October 21, 2010


OK, so you can't really shrink people like they show in movies. But here's a fun experiment you can do with something that actually does shrink.

What you'll need:
Foam plastic plates
Oven set to 350o
Oven mitts

Cut out small round or rectangular pieces from the flat bottom of the foam plates. Draw pictures on them with the markers. Arrange them on a piece of foil so that they are not touching, and heat in the oven for 4-5 minutes, or until they have shrunk. Take the foil out of the oven carefully using the oven mitts and let the shrinkies cool. You will see a miniaturized version of what you originally drew!

So, why does this kind of shrinking work? The foam has a Swiss-cheese-like structure, with lots of air holes. When you heat the piece of foam, the air bubbles collapse, and you end up with a solid piece of plastic. You have actually changed the density of the plastic, by decreasing the volume, keeping the mass (weight) the same.

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