The image above is a **semicircle **with a radius of 7 cm.

To compute the centroid or centre of gravity of a semicircle, you need one essential parameter and this parameter is the radius of the semicircle.

The formula for calculating the centroid or centre of gravity of a semicircle is:

C.G.= ^{4r} / _{3π}

Where:

r = Radius of the Semicircle

π = Mathematical Constant = 3.142 (approximately)

Let’s solve an example:

Find the centroid or centre of gravity of a semicircle where the radius is 7 cm.

From the example above,

r = radius of the semicircle = 7

C.G. = ^{4(7)} / _{3π}

C.G. = ^{28} / _{9.4247}

C.G. = 2.97

Therefore, the **centroid or centre of gravity of the semicircle** is **2.97**.

Nickzom Calculator – **The Calculator Encyclopedia** is capable of calculating the centre of gravity of a semicircle at a distance from its base measured along the vertical radius.

To get the answer and workings of the **center of gravity** or **centroid **of a semicircle using the **Nickzom Calculator – The Calculator Encyclopedia. **First, you need to obtain the app.

You can get this app via any of these means:

**Web** – https://www.nickzom.org/calculator-plus

To get access to the **professional **version via web, you need to **register** and **subscribe **for** NGN 1,500 **per** annum** to have utter access to all functionalities.

You can also try the **demo **version via https://www.nickzom.org/calculator

**Android (Paid)** – https://play.google.com/store/apps/details?id=org.nickzom.nickzomcalculator

**Android (Free)** – https://play.google.com/store/apps/details?id=com.nickzom.nickzomcalculator

**Apple (Paid)** – https://itunes.apple.com/us/app/nickzom-calculator/id1331162702?mt=8

Once, you have obtained the calculator encyclopedia app, proceed to the **Calculator Map, **then click on **Mechanics**** **under the **Engineering** section

Now, click on **Centre of Gravity** under **Statics**

Now, click on **Centre of Gravity of a Semicircle**

The screenshot below displays the page or activity to enter your value, to get the answer for the centre of gravity of a semicircle according to the respective parameter which is the radius of the semicircle (r).

Now, enter the value appropriately and accordingly for the parameter as required by the **example** above where the **radius of the semicircle** is **7**.

Finally, click on **Calculate**

As you can see from the screenshot above, **Nickzom Calculator** – The Calculator Encyclopedia solves for the centre of gravity or centroid of a semicircle and presents the formula, workings and steps too.