初三物理第八章电流的定律和第九章电功电功率两章教材,是直流电的基本定律在初中阶段所涉及的内容。它的基本特点是:基本概念多,如电量、电流强度、电压、电阻、电功、电功率等都是电学的基本物理量和基本概念,其数量之多,地位之重要,都居各章节之首; The physics of the third chapter, the current law of the eighth chapter, and the ninth chapter of the textbook, Electrical power, are the contents of the basic law of DC in the junior high school. Its basic characteristics are: basic concepts, such as power, current intensity, voltage, resistance, electrical power, electrical power, etc. are all basic physical quantities and basic concepts of electricity, and their number and position are important, ranking first in each chapter. ;