Finally, I can't talk about cheap physics apparatus without including HarborFreight.com. Worth a visit for the $10 digital multimeter alone ($3 on sale), $20 sound meter, $11 IR thermometer, and many other inexpensive geeky goodies. Every lab group can have cheap durable voltmeters and ammeters as necessary. Our introductory labs stock about four dozen of these meters, and while we blow lots of fuses we have yet to electrically destroy one (though several have met their physical doom for the good of the discipline). http://harborfreight.com, search on the appropriate keyword.

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