Recent content by barns

Thanks for replying. I understand that when the disc peripheral speed equals (-) the disc translational speed, the disc spin and translation speeds are constant (in our perfect lossless system). What I don't understand is how to calculate that *actual* speed. My thought is that spin KE...

1. Problem: Determine the final translational speed of a spinning disc that is dropped on an infinite horizontal plane. Think of spinning up an automobile wheel suspended over a road (wheel spinning normal to the road), then dropping the wheel on the road. When the wheel rim touches the road...

Graphite depends on having minuscule amounts of water in its environment to maintain its lubricity. In a very dry environment or one hot enough to drive off intercalated water, it becomes quite abrasive. This was first found, IIRC, in WWII when graphite brushes in electric motors flown at...