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Fire Syringe

Let’s take a look at something called a Fire Syringe. It is a tube with a piston that has an object, such as a small wool strand, in it. When you press down on the piston, the wool disappears in a flash of light!

This is actually the Ideal Gas Law in action (PV=nRT). The pressure increases so quickly when the piston compresses that the temperature rises tremendously. Thus, the wool ignites.

Cotton has a low specific heat, which is why we use it in oven gloves or in clothes like sweatshirts. Why would we use it in heat transfer then?

By limiting the mass of the cotton it will still conduct heat quickly and will, since it is also combustible, ignite when it hits a high enough temperature. Many materials could work here. You can see this in action at the following link:
http://www.youtube.com/watch?v=OEwlwYqPIAw

On to page 7!