Product Name: KX1937 Self-made Rainbow Spinner
Model Number: KX1937
Size: 60*60*35 mm
Weight: Approximately 60g
Material: Metal components + paper
Color: 7 Colors
Battery usage: No
Packaging: 1000 pcs
Box dimensions: 600*450*550mm
The top is an ancient Chinese children's toy that spins on the ground. As it rotates, it not only turns around its own axis but also moves in a conical shape around a vertical axis. To keep the top upright, external force must be continuously applied. Once the external support is removed, the top will quickly fall because its base is too small to support its own weight. The duration of the top’s rotation depends on the distance from the base to the ground, the amount of force applied during rotation, the contact area between the base and the ground, and the friction force.
Experimental Principle:
Why can a top rotate without falling? This is a dynamic unstable equilibrium. When the top is rotated under force, the total centrifugal force in all directions reaches a balance, allowing it to stand at the axis for a while. However, factors such as air resistance, ground friction, or the center of gravity of the top cause the rotating force to gradually weaken until it disappears, and then the top begins to wobble and fall.
Teaching Objectives:
1. Be able to apply the knowledge of light dispersion learned to create various spinning tops; make discoveries during the process and record and present one’s research findings in a timely manner.
2. During the process of making and playing tops, students' sense of cooperation is cultivated.
3. By playing with spinning tops and conducting light synthesis experiments, understand the synthesis of light, as well as the relationship between light dispersion and synthesis.
Teaching key points and difficulties:
1. Be able to apply the knowledge of light dispersion learned to create various spinning tops; make discoveries during the process and record and describe one’s research findings in a timely manner.
2. By playing with spinning tops and conducting light synthesis experiments, understand the synthesis of light, as well as the relationship between light dispersion and synthesis.
Teaching aids:
Material Package
Blackboard Design:
1. Light mixing and the persistence of vision
2. Synthesis of the three primary colors of light
1. Create a scenario to help students perceive the problem:
Teacher: Who has played with a top?
Free speech is allowed.
Teacher: Is the top spinning fun?
Life: Fun.
Teacher: How is it fun?
Free speech is allowed.
Teacher: How do you play with a top?
Free speech is allowed.
As a child, I played with spinning tops. Has anyone played with other types of tops?
Free speech is allowed.
Teacher: Did you make it yourself, or did you buy it?
Free speech is allowed.
Teacher: Do you want to make one yourself?
Life: Want.
Teacher: So for today’s class, let’s make a spinning top. What will we use? It’s very simple—a piece of paper. I believe you will be able to make one after this lesson.
2. Exploration and experience, problem-solving:
Activity 1: Making spinning tops.
Teacher: (First, showing several already made top spins) Does anyone know how to make a top spin? Who would like to share their idea?
After allowing free discussion, the teacher demonstrates and provides further explanations on the methods and steps of making them. Then, students share the ways they know to make spinning tops. Teacher: Now, raise your hand and create your own spinning top!
Lively hands craft spinning tops.
During the production process, students should be reminded about safety precautions when using scissors.
Teacher: Don’t forget to give the top to the spinning top some beautiful colors!
Color the spinning top.
Coloring requirements:
① Each team is required to paint a top according to the color ratio provided in the textbook.
② Then, students can color the completed top in any way—two, three, or more colors.
Activity Two: Spin the Top.
Teacher: Great job, students! The spinning tops you made are really beautiful. How can we make the tops spin more steadily?
Answer freely.
Teacher: Now, everyone can get involved and make them rotate.
(1) Repeat the experiment with spinning top paints different colors, and observe what color the spinning top appears to be when observed carefully?
(2) Guide students to record the observed phenomena promptly for future sharing and exchange.
Group report and discussion.
Teacher’s summary: Different colors merge into one color, and seven colors turn white.
Teacher: If you want to further study this issue, you can look up more information. See if you can figure out what kind of phenomenon this is and why the eyes cannot distinguish rapidly rotating patterns. This is a phenomenon of visual persistence. (Teacher: writing on the blackboard) Rapid rotation
It looks circular. So, what applications can you think of for this persistence of vision effect?
Answer freely.
Teacher: Animated cartoons utilize human visual phenomena. So, how should we explain this mixing of colors and light? I have a top that I made myself. What color it appears to be when it spins—grayish-white, and the color seems to disappear instantly. If you’re interested, you can try making a top with rainbow colors. What color would it be when it spins? Newton once conducted an experiment like this and could explain a scientific principle. What exactly is it?
Answer by name (designated by name).
Teacher: Around the year 1666, Newton, at the age of 24, used a prism to split white sunlight into seven colors—that is, the rainbow. When he excitedly reported this discovery to everyone, he faced strong opposition. To verify that these seven colored lights could also be combined into white light, Newton conducted an experiment using a spinning top, which helped people understand his scientific discovery.
Activity Three: Let’s explore changeable light
The situation where the three primary colors of light (red, green, blue) overlap.
1. My observation record sheet (students fill it out themselves first, followed by a teacher summary)
