félkörívet

A félkörív, meaning semicircle in Hungarian, refers to half of a circle. It is a geometric shape bounded by a diameter and the arc that subtends the diameter. The arc of a semicircle is exactly 180 degrees. The straight edge, the diameter, forms a straight line through the center of the original circle, connecting two points on the circumference. The curved edge, the arc, is half of the circumference of the original circle.

The area of a semicircle is half the area of the full circle from which it is derived. If the radius of the full circle is 'r', its area is πr². Therefore, the area of a semicircle is (1/2)πr². Similarly, the perimeter of a semicircle consists of the length of the diameter (2r) plus half the circumference of the full circle (πr), making the total perimeter 2r + πr.

Félkörívek appear in various contexts. Architecturally, they are commonly seen in arches, windows, and doorways, providing both structural support and aesthetic appeal. In engineering, they can be found in the design of bridges, tunnels, and tools. In everyday life, a semicircular shape can be observed in objects like a dome, a half-moon, or even a specific type of haircut. The mathematical properties of a félkörív are fundamental in geometry and calculus, particularly when calculating volumes and areas of more complex shapes.