Costruzione e geometria · Glossario
What is Circumference?
Definizione rapida
The perimeter of a circle — the total distance around it. C = 2πr, or C = πd.
Spiegazione completa
Circumference is the perimeter of a circle, equal to 2πr (where r is the radius) or πd (where d is the diameter). π (pi) is approximately 3.14159, an irrational number with infinite non-repeating decimals. The relationship C/d = π is one of the most fundamental in geometry — it is the same for every circle, regardless of size. Circumference is used for: fence around a circular garden, belt length for a pulley, the equator's length (~40,075 km), the distance a wheel travels in one rotation. The concept of π was independently discovered by many ancient cultures (Babylonians, Egyptians, Indians, Greeks).
Calcolatori correlati
Calculators that use or explain Circumference.
Termini correlati
More from Costruzione e geometria
Area
The amount of 2D space inside a shape, measured in square units (m², ft², acres, hectares).
Volume
The amount of 3D space inside a shape, measured in cubic units (m³, ft³) or in liters/gallons.
Perimeter
The total distance around the outside of a 2D shape. Measured in linear units (m, ft).
Slope
The steepness of a line, calculated as rise over run. Slope = (y₂ - y₁) / (x₂ - x₁).
Density
Mass per unit volume, typically in kg/m³ or g/cm³. Different materials have characteristic densities.
Last reviewed: June 15, 2026 • Category: Costruzione e geometria