The Validity of 'Step-by-Step' Science Study by the School Text Books : About Electromagnetism Chapter in Text Books of Elementary School, Junior High School and Senior High School

摘要

In an open science class of a junior high school, I had questions about the teacher's description about the electromagnetism phenomenon. After the class, to my questions the teacher replied saying, "I followed the descriptions in the teacher's guide book !" Since then, it has been my concern for thirty years and so. It is about "Fleming's left hand rule" on electromagnetism. In the text books of junior and senior high school, it is explained that force comes from the interaction between the magnetic field by the electric current and another magnetic field by the magnet. And in the composite magnetic field with these two sources, magnetic-field of the wire on one side is high density, on the other side it is low, so, 'force' rises from high density to low. I think this explanation is not appropriate to teach this phenomenon on each grade. My opinion is that the studying sequence about this electromagnetism unit is better to be understood basically with "Fleming's left hand rule" and "Lorentz force"