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Circumference of a Circle

In 240 B.C., Eratosthenes, a Greek mathematician, was the first to calculate the Earth's circumference. A circle's circumference is equal to its perimeter. It is the whole length of the circle's boundary. The circumference of a circle is equal to the product of the constant t π and the circle's diameter. This measure of the diameter of a circle is required for a person strolling through a circular park or a circular table to be bordered.

The Latin prefix circum- means “around or round around,” and is used to produce the term circumference. As a result, every term produced with this prefix relates to either anything literally round—such as a circus ring—or something metaphorically round, such as an activity or the conditions surrounding someone or something—such as their circumstances. A chord is a line that connects two sites on the circle’s perimeter but does not pass through the centre. The circumference of the circle is the length of the round edge that forms the circle, and the area of the circle is all the space enclosed by the circle’s edge, including the circle’s centre.

Definition of Circumference of a Circle

“The circumference of a circle is the length of its circumference. We can determine the circumference of a circle in terms of centimeters, meters, or kilometers if we open a circle and measure the boundary like we would a straight line.”

Circle’s three most important components

  • Center: The circle’s centre is a location that is a constant distance from any other point on the circumference.
  • Diameter: The diameter is a line that joins the circumference at both ends and must pass through the centre of the circle.
  • Radius: The radius of a circle is the distance between the circle’s centre and any point along its perimeter.

Formula for the Circumference of a Circle

The following equation expresses the relationship between a circle’s circumference and radius R.

Radius = Circumference/2π

Where is a constant that is about 3.14159265…

When the circumference of a circle is known, we use the formula to compute the radius or diameter:  Radius = Circumference/2π

How do you calculate the circumference of a circle?

Although the circumference of a circle is equal to the length of its boundary, it cannot be determined using a ruler (scale) as other polygons can. 

The radius of the circle is required to calculate the circumference:

  • To find the diameter, divide the radius by two.
  • To get an estimate, multiply the value by, or 3.14.
  • That’s all; you’ve discovered the circle’s circumference.
  • You can also use the diameter of the circle:
  • 3.14 Or π, is the diameter multiplied by.
  • The circumference of the circle is the outcome.

Example of Circumference of a circle

Find the Circumference of a circle radius 9

Solution: The formula for the circumference of a circle is = 2πr

The radius =9cm is given,

Circumference =2πr

=2×3.14×9

=6.28×9

As a result, the circle’s circumference is,=56.52cm

Conclusion

In this article we learn, there are a lot of circles in life (and semi-circles). As a result, the circumference of a circle equation can be applied to any circle-related problem. Because circumference is a length measurement, there are two types of challenges that will need you to calculate the circumference of anything circular. To begin, understanding a circle’s radius can be used to make something circular. Second, if the circle is moving at a constant pace, the circumference can be used to calculate how far the circle will move in a given amount of time.

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Frequently asked questions

Get answers to the most common queries related to the IIT JEE Examination Preparation.

Why is a circle's circumference 2πr?

Ans. The ratio of a circle’s circumference to its diameter is known to be fixed, and its value is 3.14159̷...Read full

Is a circle's circumference always 360 °?

Ans. The 360º arc of the curve that encircles a circle is another way to conceive of it. As a result, the circumfer...Read full

Is 180 ° a complete circle?

Ans. The circumference of a full circle is 360 ° ...Read full

What is the value of 2πr in a circle?

Ans. Circumference is calculated using the formula C =  2πr,...Read full

Calculate the circumference of a circle with a radius of 28 cm.

Ans. The circle’s radius is given to be 28 cm. We’ll use the circumference formula to get the circleR...Read full

Is circumference measured in cm2 or cm?

Ans. To find a circle’s circumference, multiply its diameter by pi, which is 3.14. For example, a circle with ...Read full