In mathematics or geometry, a circle is a form of an ellipse with zero eccentricity and two foci that coincide. A circle is frequently referred to as the locus of points drawn equally distant from its center.

Have you ever heard of the term radius? The radius of any circle is defined as the distance that lies between the center of the circle to the outer boundary of the circle. The radius of a circle is denoted by the letter ‘R’ or ‘r’ whereas the diameter of a circle is denoted by the letter ‘D’ or ‘d’.

The diameter of a circle is defined as the line that is present in every circle and it is generally the distance between the center of the circle and the outside line of the circle. Every circle has a diameter, and this diameter is known to divide the circle into two parts each equal in size.

In this article, we are going to discuss what is the radius of a circle, diameter of a circle, and more.

**Calculating Radius of Circle**

A circle is defined as a fundamental 2D shape whose radius is measured. The rings divide the plane into 2 sections: inner & outer. It is analogous to a line segment. Suppose that the given line segment has been twisted till its ends meet. Set up the loop so that it is properly circular in shape.

We already know about the radius of a circle and the symbol we used to denote the radius. Now, let’s know the radius of a circle.

Radius = Diameter/2

If we have been given the value of the diameter of a circle, we can substitute it in the formula & we can find the radius of the circle.

Whereas to find the diameter of the circle, we need to calculate it using the formula = Radius*2

**Examples**

**Question 1:** Rahul made a circle using a compass and a pencil. The radius of the circle made by him is 5 cm. What is the diameter of the circle made by him?

**Solution:** We know that the radius of the circle equals 5 cm.

Now, we can calculate the diameter using the formula = Radius *2

Therefore, the diameter of the circle is equal to 10 cm.

**Question 2:**Priyam made a circle using a compass and a pencil. The diameter of the circle made by him is 10 cm. What is the radius of the circle made by him?

**Solution:** We know that the diameter of the circle equals 10 cm.

Now, we can calculate the radius using the formula, R = Diameter/2

Therefore, the radius of the given circle is equal to 10/2 = 5 cm.

The topic circle and how to calculate the radius & diameter of a circle is a very interesting topic. To know more and solve more examples, you can visit the Cuemath website.

**Math Worksheets**

To grasp the field of arithmetic, you must constantly practice a wide range of sums from many areas. Math worksheets are an excellent method to practice various sums from a range of topics. Problems begin at the very simple level and progress to the middling level, and eventually to the complicated level. Math worksheets can help you cover practically all of the major ideas within a specific chapter. Cuemath’s site allows you to practice a variety of math worksheets. Teachers at Cuemath often perform activities such as math worksheets, math games, arithmetic puzzles, and so on to ensure that you have a thorough grip and knowledge of the topic.