Half a part of any kind of circle is recognized as a semicircle and is created by cut a entirety circle along the diameter. Various parameters concerned a semi-circle like a diameter, area, the perimeter deserve to be calculated making use of semicircle formulas. The diameter of a circle divides the circle into two equal semicircles. The area of any semicircle is fifty percent of the area the a circle. Permit us recognize the semicircle formulas utilizing solved examples in the complying with section.

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What AreSemicircle Formulas?

The semicircle formulasinclude the formulas to calculation the area and perimeter (or circumference) of a semicircle. This formulas are based upon the truth that a semicircle is fifty percent a portion of a fullcircle.


Area that a Semicircle Formula

Since we know that a semicircle is fifty percent a circle, the semicircle area will certainly be half of the area the a circle.So, the area of a one isπR2where R is the radius the the circle. Theareaof a semi-circle describes the region or inner space of the semi-circle. Hence,

Area that a Semicircleformula =πR2/ 2.


π(pi) is 3.142 approximately.

Perimeter the a Semicircle Formula

The perimeter the a semicircle formula is usedto calculation the perimeter that a semicircle. We mustknow one of two people the diameter or radius of a circle together with the length of the arc. Come evaluatethe length of the arcof the semicircle, we should calculatethecircumference the a circle.

The circumference of a circle is C = πd or C = 2πr,Using the value of Cwe can determine the formula for the perimeter that a semicircle i m sorry is calculated as the sum of half of the circumference of the circle and also diameter the a circle.The perimeter of a semicircle formula = (πR+ d) or (πR+ 2R)units, orR(π + 2).


π(pi) is 3.142 approximately.

Let united state see how to usage these semicircle formulas in the complying with section.

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Examples ~ above Semicircle Formula

Let united state take a look in ~ a couple of examples to better understand the recipe of the semicircle.

Example 1:Using the semicircle formula calculate the area the the semicircle whose diameter is 12 in. Express her answer in regards to π.


To find: The area of the semicircle,Given: Diameter that the semicircle =12 inRadius the semicircle = 12/2 = 6 inUsing semicircle formulas,Area that Semicircle = 1/2× (π r2)Area = (π × 62)/2=36 π/2=18π in2

Answer:The areaof the semicircle is18π in2.

Example 2:If theradius the a semicircle is 7 units,then utilizing the semicircle formula find its perimeter.


To find: The perimeter that a semicircleGiven:The radius ofsemicircle = 7 unitsUsing the perimeter/circumference of a semicircleformula,Perimeter of a semicircle =πr + d =πr + 2r= 7 × 22/7 + 14 units

Answer:The perimeter the thesemicircle is 36units.

Example 3: Using the semicircle formulas calculate the one of a semi-circle who diameter is 8 units.


To find: The circumferenceof a semicircleGiven:The diameterofsemicircle = 8 unitsRadius = 8/2 = 4 unitsUsing the one of a semicircleformula,Circumference the a semicircle =πr + d =πr + 2rC = (3.14)× (4) + 2 (4)C = 20.56 units.

Answer:The one of thesemicircle is 20.56units.

FAQs ~ above SemicircleFormulas

What Is the Area of a Semicircle Formula?

Theareaof a semi-circle refers to the full amount that inner space of the semi-circle. That is express as,Area that a Semicircleformula =πR2/ 2.Where,

r = R is the radius of a semicircleπ(pi) is 3.142 approximately.

What Is the Perimeter of a Semicircle Formula?

The perimeter the a semicircle formula is characterized as the sum of half of the circumference of the circle and the diameter the a circle. That is to express as

The one of a circle is C = πd or C = 2πRThe perimeter the a semicircle formula = (πR+ 2R)units, orR(π + 2).

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r = R is the radius the a semicircleπ(pi) is 3.142 approximately.d = Diameter of a semicircle

What are the recipe of Semicircle in Geometry?

The formula to calculate thearea of a semicircle through radius 'r' is provided as, Area that Semicircle = 1/2× (πr2) square unitsThe formula to calculation the perimeter/circumferenceof a semicircle with radius 'r' and also diameter 'd'is provided as,The perimeter the Semicircle= πr + d units

What Is the Difference in between the Area the a Circle and Semicircle Formulas?

Thearea the the circleformula is expressed as A =πr2. Whereas, the area of the semicircle is half the area that the circle. Therefore, the area that the semicircle is πr2/2, wherein 'r' is the radius.The areaof a semicircleis express in square unitslike in2, cm2, m2, yd2, ft2, etc.