Before finding out all one formulas, let united state recall what is a circle. Acircle is characterized as the collection of points placed at an equal street from a fixed point in a plane. The resolved pointis referred to as the center of the circle.Radiusis the distance from the facility of a circle come the border of the circle.Let us know all circle formulas using resolved examples.

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What AreAll circle Formulas?

Parameters likearea,circumference, theradius the a circlecan be calculated making use of allcircleformulas. Differentcircle formulasto calculate different parameters the a given circle have the right to beexpressed as

Circumference of a CircleC = 2 × π × rArea the a CircleA = π × r2


r = radius the the circled = diameter of the circlec = circumference of the circle


List of every Circle Formulas

Given below is the list of every circle formulas because that your basic calculations because that a circle is radius 'r'.

ParametersCircle Formulas
Diameter of a one formula

D = 2 × r

Circumference the a circle formula

C = 2 × π ×

Area the a circle formulaA = π × r2

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Examples top top CircleFormulas

Let us resolve some interesting difficulties using the perimeter of the circle formula.

Example 1:Find the area the the circular park who radius is same to 200m.


To find: Area the a park.Given:The radius the the park =200 mUsing among the all circle formulas (area the a circle formula),Area the a Circle= π ×r2=π ×2002=π × 40000

Answer: The area that thecircular parkis 40000π m2.

Example 2: making use of the perimeter the a circle formula, find the radius that the circle having actually a circumference of 100 in.Solution:

To find: Radius the circle

Given: one = 100 in

Using perimeter of a one formula,The perimeter of the one or circumference = 2 π r

2 π r = 100

2 × 22/7 × r = 100

r = 100 × 7 / 44

r = 15.909 inch

Answer: Radius of one = 15.909 in

Example 3: The radius the a circle is 8in.Using thecircle formula, calculation the circumferenceofthe circle.


To fine: one of circleGiven: r = 8inThe perimeter of one formula =2πrC = 2×(22/7)× (8)Answer: The one of a one is 50.28inches.

FAQs on one Formula

What Is the Perimetera Semi-Circle Formula?

The Semi-circleis fifty percent of the full circle. For this reason if the perimeter that the semi-circle formula is 1/2 (2πr) =πr units.

What Is the Diameterof one Formula?

The diameter that a one formula is identified as twice of a radius.Hence, D = 2r, whereby r is the radius that a circle.

What Is the Perimeter of one Formula?

The perimeter of the one formulais offered as2 π r,where 'r'is radiusandπ is constant with value (3.14 or 22/7).

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How To calculate Radius using Circle Formula?

The circumference of the circle formula is given as2 π r. If we know the value of the circumference ofthecircle, then by substituting the valuein the formula we deserve to calculate the radius, 'r'.r = (circumferenceof circle)/2 π.