Knowledge and skills:
Let students know that the mirror can reflect light, and you can see the image of the object in the mirror.
Process and method:
Cultivate students' experimental ability and do experiments of specular reflection and imaging;
Can tell the application of mirror in life.
Emotions, attitudes and values:
Cultivate students' interest in inquiry.
Second, the focus and difficulty of teaching
A mirror can reflect light, and images of objects can be seen in the mirror.
Third, teaching preparation.
1. Grouping experimental materials: flat mirror, flashlight;
2. courseware.
Fourth, the teaching process
(1) import
Teacher: I put my flashlight in this place. Can you shine on the blackboard without using other tools? The flashlight shines directly on the ceiling.
Health: No, because light travels in a straight line and can't turn.
(2) Activity 1: Challenge 1: Shine the lamp on the blackboard.
Teacher: Then can you turn the light around? If you had to choose a tool, what would it be?
Health: I will choose a mirror.
Teacher: Why?
Health: Because the mirror can reflect light.
Teacher: Who will demonstrate how to shine light on the blackboard? (Ask a classmate to give a demonstration on stage)
Teacher: Why did you move the mirror?
Health: Because I want to find out where the light is reflected. Listen, that's enough.
(3) Activity 2: Draw the reflected rays of light.
Teacher: Well, that's great! This classmate has been moving the mirror just now, saying that he is looking for reflected light. How does a mirror reflect light? Does it have some rules? Can you draw it?
1, work in groups, and draw the law of light reflected by the mirror.
2. Panel report
3. Summary: The angle between the incident light and the mirror is the same as that between the reflected light and the mirror.
(4) Challenge 2: Put the lamp behind the box.
Put the flashlight on one side of the box, how to make the light shine on the back of the box?
1. Discuss how many mirrors can be used.
2. Experiment in groups and draw the position of the mirror and the reflection route of the light.
3. Report of the Panel
4. Summary
(5) Imaging of the mirror
Teacher: Just now, students used mirrors to reflect light, and we often use mirrors in our lives. For example, when we brush our teeth and wash our faces in the morning, we all take a photo because the mirror ...
Health: You can look at yourself, the role of imaging.
Teacher: Do you know that objects and images in the mirror are the same?
1, guess what F looks like in the mirror?
2. Experiment in groups and draw images on paper.
3. Panel report.
4. Summary: The image in the mirror is the same size as the real thing, but in the opposite direction.
(6) Where do we use mirrors in our daily life?
Five, blackboard writing:
mirror
1, reflected light
2. Imaging and object: same size, opposite direction.
Sixth, teaching reflection.
Because in the previous content, students have learned that light travels along a straight line, and students often play games with mirrors to reflect sunlight in their daily lives, so they have a better understanding of light reflection. Therefore, in the content of this class, all the activities I designed are made in class by using students' existing incoherent life knowledge, displayed with pictures, and found out the internal laws by using legends.
In the activity of looking for the reflection law of light, at first I was afraid that students could not find the internal law in a short time. Although they could easily say that light was reflected on the other side of the incident light, in actual teaching, many students said that the angle between the incident light and the mirror was the same as that between the reflected light and the mirror, and it was easy to mark it on the map, so I did not introduce the concept of normality into teaching, so as not to cause confusion of students' thinking.
The imaging of mirrors is not discussed in detail in this book. I added, "Is the image in the mirror consistent with the real thing?" Activities, causing students to explore common phenomena in life and prove their ideas. At the same time, it also strengthens students' understanding of the application of rear mirror in life.