Understanding Introductory Mechanics - John McClelland - Bog

Physics teaching should be informed by four precepts: A single concept should have a single definition and should be represented by a single symbol; separate concepts should have separate definitions and symbols; Vector characteristics should not be ascribed to scalar quantities and vice versa; vector and scalar quantities cannot, so should never, be equated; Operational definitions should be distinguished from conceptual definitions; Something that is difficult to explain and to learn should not be replaced with something that is easy to explain and to learn, but that is not valid. This book applies these precepts to Introductory Mechanics.