<snippage of geeky physics stuff> Wow, some of this is actually coming back to me. It's been awhile since Physics-I at the U (I had that older German prof, goofy guy...Hans or something) We did some calculations in class once about a (solid-frame all-steel full-sized) Cadillac colliding head-on with a VW bug. I don't remember any of the numbers, but the Caddy driver ended up calling the ambulance/coroner for the VW driver, who would have been catapulted 60+ feet through the windshield (assuming no seatbelt, no windshield). Made me feel a lot better about driving my (solid-frame, all-steel, full-sized, '89 Crown Vic) Shaggin' Wagon. It would be interesting to see a comparison between a spinning CD and the spinning blade of a radial arm saw. Granted, the blade is much heavier than a CD, but I bet the CD spins a lot faster > A 1 gram chunk at 65.3 m/s would have 2.1 joules of energy. > While the disk is spinning, its kinetic energy = 1/2 I w^2. I, > the moment of inertia is 1/2 m r^2. So, > KE_rot = 1/2 (1/2 m r^2) (v/r)^2 = 1/4 m v^2 = 16 J , with > a CD mass of 15 grams. For comparison, this is the same as the > kinetic energy of a golf ball going 59 mph (26 m/s) - which would > be slow for a golf ball. > > Sorry for the abundance of details. _______________________________________________ TCLUG Mailing List - Minneapolis/St. Paul, Minnesota http://www.mn-linux.org tclug-list at mn-linux.org https://mailman.real-time.com/mailman/listinfo/tclug-list