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The air moving devices in the iMac G5 are called centrifugal (or sometimes radial) fans.

The air moving devices found in most computers are called axial fans.

There are a few other basic fan designs, but you probably won't find them in a computer.

A "blower" is a fan-and-housing assembly, and can contain any type of fan.

This material will be on the final exam, and will make up 20% of your grade for the semester.
 
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