电流的强弱（Current intensity）.doc

电流的强弱（Current intensity） Textbook analysis The electric current is out of sight, and the intensity of the current is known only indirectly through other means. The concept of the current, the unit, and the common current values in life are derived from the current flowing through the flashlight and the current flowing through the car lights, which are different in intensity. Then tell the students that the current in the circuit can be measured with an ammeter. Guide students how to connect the ammeter and how to read it. I is the sign of the physical quantity of the current, and A is the symbol of ampere, the unit of electric current, which is very confusing for junior high school students, and should be distinguished from each other in teaching. Reading the readings of electric meters is a basic skill that must be possessed in electrical experiments and a key point in teaching. How to connect ammeter into circuit is a difficult point in Teaching Learning situation analysis Electric current intensity is the second physical quantity that students learn in physics learning (the first is temperature). Students learning of physical quantity is at the enlightenment stage. Therefore, the understanding of the quantity of current is the first difficult point of teaching. Although the students connect to a simple circuit, the ammeter has three terminals, which take into account the range and the direction of the current. Therefore, connecting the ammeter to the circuit is second teaching difficulties. The class of the students I teach is poor, and it is difficult to carry out the conditions of analogy, practice and cooperative study teaching method The experimental method, discussion method, observation method, coaching method preparations Flashlights, toys, cars, batteries, switches, wires, light bulbs, circuit boards Three summary In this lesson, we have mainly studied the following: 1. current can be used to indicate the strength of an electric current. 2. correct connec