2、

Number of battery parts

3, coil turns

Exploring factors

Hypothesis: and

Related factors. Invariant factors of experimental design:

Changing factors:

Change the factor for the first time to pick up the number of pins

second time

the third time

conclusion

The magnitude of electromagnetic force and

Related factors.

Activity 1: Make simple electromagnet materials: enameled wire and iron core. Objective: To master the manufacturing method of simple electromagnet. Methods: 1. One-way winding of iron core with enameled wire. 2, when making electromagnet, write down the number of coil turns. 3. Leave some at both ends of the enameled wire.

Activity ②: Explore what factors are related to the magnetic force of electromagnet Purpose: 1. Design the experimental scheme. 2. We can draw a conclusion from the analysis of experimental data. Material: dry battery, conductor, enameled wire, iron core, pins.

Step: 1. Design scheme.

2. Choose a scheme for the experiment.

3. Record data.

4. Analyze the data and draw a conclusion.