When a circle is cut along its centre line or the diameter, the resultant figure gives us two congruent semicircles. In other words, a semi-circle is exactly half of a circle. The perimeter, i.e., the length of the boundary of a semicircle is calculated by the formula (d+ rπ), where d is the diameter, and r is the radius of the semicircle. The area of a semicircle is half that of the area of a circle and is given as ½πr², where r is the radius of the semicircle.

**Examples of Semicircle**

### 1. Protractor

A protractor is a geometric construction tool that is shaped like the English alphabet ‘D.’ It is a prominent example of the semicircular objects used in our daily life.

### 2. Japanese Fan

A Japanese fan is yet another example of the semicircle geometric shape present in real life. It consists of a straight line and a curve attached to both ends of the line.

### 3. Analogue Speedometer

Analogue speedometers typically consist of a needle and a graduated scale. Typically, such speedometers are constructed in the shape of a semicircle. Hence, one can easily locate the semicircular geometric shape in real life by looking at the speedometer of their car or motorcycle.

### 4. Windows

Some of the windows located on the top of the doors are constructed in the shape of a semicircle. This adds an attractive look to the house.

### 5. Tunnel

If you try to trace the outline of a tunnel, you can easily observe its semicircular shape because it consists of a curve that is attached to a straight line.

### 6. Taco

Taco is a popular Mexican cuisine. It consists of tortilla bread that is bent from the middle and has food stuffing present in between its two halves. If you look at a taco from the side, you can easily observe the semicircular geometric figure in real life.

### 7. Napkin Holder

Most of the napkin holders placed on the top of dining tables consist of two semicircles attached to each other with the help of a rectangular strip.

### 8. Door Mat

Doormats are available in a variety of shapes and sizes. The most popular shape among them is a semicircle.

### 9. Pizza

If you cut a circular pizza along its diameter, you will get two semicircles that are equal in shape and size.

### 10. Moon

If you observe the shape of the moon when it is in the first or last quarter, you can see a shape that roughly resembles a semi-circle. Hence, the moon is a prime example of semi-circular objects present around us.