Does anyone know a good, cheap, source for stainless steel ball bearings. I'm looking for roughly 1/2" diameter, but can be flexible on the size.

What resources do you find most useful when preparing lessons, labs, etc? If possible, please link directly to the website using the following notation: [link name](http://exampl …

What is the typical coefficient of friction between a tire and the road? It seems that with cars now doing 0-60mph (0-~27m/s) in shorter and shorter times that the coefficients mu …

I'm looking for more Newton's Third Law activities that get students involved. So far I have: Students pull on each other using rubber bands Students push against each other usi …

For those who may be interested, students have created a Physics In Action podcast, which is available for free from the iTunes Store (click here). The podcast includes standard e …