Area of a Circle Conversion Teaching Aid

🧮 Circle Area Conversion Aid | From Circle to Rectangle, Understand πr² at a Glance

This is a mathematical teaching aid model used to explain the derivation of the circle area formula
By dividing a circle into 16 sectors and rearranging them into an approximate rectangle, it helps students intuitively understand:

✨ Core Principle

Circle Area ≈ Area of Approximate Rectangle = πr × r = πr²

In the disk state, the formula for the circumference of a circle can be observed: C = 2πr
When the sectors are arranged alternately into a rectangular container, the length of the rectangle is approximately half the circumference of the circle, which is πr, and the width is the radius r, so the area is πr²

📘 How to Use

1. Identify the Disk: Observe the circumference marking on the circular container and understand that the circumference of the circle is 2πr
2. Magnetically Form a Circle: Attach the 16 sectors to the disk to form a complete circle
3. Unfold the Slices: Alternately unfold the slices, one up, one down, so that the edges gradually approach a straight line
4. Place into the Rectangular Plate: Magnetically place the slices into the rectangular container, observing that the length is approximately πr and the width is r

🌟 Model Highlights

🧲 Magnetic Structure: Both the circular and rectangular plates can be stably adsorbed
🎨 Two-Color Sectors: Alternating colors make it easier to observe the slice rearrangement process
📐 Formula Visualization: From circumference 2πr to area πr², the logic is clear
👩🏫 Suitable for Classroom Demonstration: Ideal for upper elementary grades, middle school mathematics, parent-child teaching, and popular science displays
🖨️ Suitable for 3D printing: The parts have a clear structure, making arrangement and demonstration very convenient

📷 Product Usage Instructions Diagram

From disk, magnetic circle formation, unfolding slices, to placing into the square plate, fully demonstrating the derivation process of the circle area formula

✅ Target Audience

• Mathematics teachers for classroom demonstrations
• Parents for parent-child teaching
• Students to understand the circle area formula
• Educational 3D printed model collection

🖨️ printing Instructions

• 🧩 Recommended to use separate parts printing
• 🎨 plate 1: You can directly print two colors of circular slices and the circular base
• 📦 plate 2: print the rectangular container
• 🧲 After printing: Install magnets according to the magnet holes to switch between circular and rectangular demonstrations (use 5mm*3mm magnets) Using magnets provides a better effect, but not using them does not affect usability
• ✅ Recommended for multi-color printing: Two colors of sectors make it easier to observe the slice rearrangement process
• 🖨️ Notes: If some adjacent circular slices cannot be unfolded after printing, you can use the edge of the heatbed to cut into the interface between the two circular slices to separate them

Transform abstract formulas into tangible, interactive mathematical models. 🌈