Online Education Learn About Various Parts of a Circle Like Radius in Depth! Team TechagerJune 24, 202202.8K views In mathematics, one of the interesting modules is geometry and in geometry there are different shapes. One among the popular shapes is the circle and it is derived from the Greek term ‘kirkos’ which means the ring or a hoop. In the circle, different parts of circle are included like the radius, diameter, circumference and many others. In this guide, we will be discussing all crucial parts like a radius of circle in depth and with complete information. Circle: The Actual Meaning if you talk about the definition of the circle, it is a ring shaped 2D figure. It is formed by the set of points that are adjacent to each other. And these set of points are equidistant from a fixed point. Hence, the ring shape is formed. That fixed point in mathematical terms is called the center of the circle. Moreover, the distance between the center of a circle and the set of adjacent points is called the radius. Twice the radius or the line crossing the circle’s center from one point to another is called the diameter. If you consider deep knowledge about mathematics, there are different regions of the circle like interior and exterior. The interior region of the circle is called the inner region that is enclosed by a circle and the outside of that is called the exterior region of the circle. Know Different Parts of the Circle All in all, the circle is a closed figure with a curved boundary and has many different parts that define its characteristics. Circumference of a Circle The boundary of a circle is called the circumference of a circle. Or else, the length of the entire circle is considered the same because it will be the exact length of the boundary of a circle. It is basically expressed in SI units like centimeters, meters, or kilometers. To calculate the length of the circle we do not have any ruler. Hence, there is a formula to measure the circumference of a circle. It is 2πr where the π (pi)=3.14. Radius of a Circle As we have mentioned, the radius of a circle is a line segment that joins the center of the circle and the random point of the circumference of the circle. According to mathematical principle, there are many radii (singular form of the radius). To calculate the radius value, if you have a diameter value given in the question just divide it by 2 and get the answer. It means d/2. And the radius is also crucial for calculating the area of a circle. Diameter of a Circle In the above information, we have expressed some information about the diameter. It is a line segment that passes through the center of a circle and meets the circumference points. According to definitions, the diameter is considered the longest chord in the circle. It’s alphabetical representation is ‘D’. Like radii, there can be an infinite number of diameters in the circle. One of the popular formulas to calculate the same is D = Circumference/π Chord of a Circle It is basically a line segment that joins the two points on the circle’s circumference. Because of this, the circle is divided into two parts called the minor segment and the major segment. You can refer to online study materials or textbooks to know what the chord actually looks like.