Understanding Circles

A circle is a set of all points in a plane that are the same distance (radius) from a central point (center).

Parts of a Circle

• Radius: Distance from the center to any point on the circle.
• Diameter: Distance across the circle, passing through the center (\(d = 2r\)).
• Circumference: The distance around the circle (\(C = 2\pi r\)).
• Area: The space inside (\(A = \pi r^2\)).

Why Circles Matter

Circles are everywhere—in wheels, clocks, pizzas, and even the paths of planets! Knowing their properties helps in fields like engineering, astronomy, and art.