Enter Circle Radius
📖 Formulas Used:
Circumference: C = 2πr
Diameter: D = 2r
Area: A = πR²
Where π ≈ 3.14159...
💡 Quick Examples:
📏 Radius 5cm → Circumference ≈ 31.42cm
📏 Radius 10cm → Circumference ≈ 62.83cm
📏 Radius 7cm → Area ≈ 153.94cm²
The diagram shows your circle with radius, diameter, and circumference labeled
⭕ Understanding Circles
What is Circumference?
The circumference is the distance around the outside of a circle. It's like the perimeter of a circle. If you walked around a circular track, you'd travel the circumference distance.
What is Radius?
The radius is the distance from the center of the circle to any point on its edge. It's exactly half of the diameter and is the most fundamental measurement of a circle.
What is Diameter?
The diameter is the distance across the circle through its center. It's the longest distance you can measure in a circle and is always twice the radius.
What is Area?
The area is the amount of space inside the circle. Think of it as how much paint you'd need to fill in the circle, or how much grass would fit inside a circular garden.