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.
