Now, for all your classroom physics demonstrations, The Ideal Scientific Equipment Company Catalog! From the Ideal Scientific Equipment Company (motto: "If you didn't get it from us, it's not IDEAL!"), you can now get your hands on proper weightless inextensible strings (in reels of 200m), frictionless planes, point particles (in all masses from 1g to 10kg), completely rigid bodies ("Have you ever had a demonstration fail due to non-rigidity of an essential part of your apparatus? An ISE rigid body NEVER flexes!"), and Occam's Razor, with its finest Swedish surgical steel blade. All the tools the theoretical physicist needs!
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