Top 10 geometry facts

Neither east, west, nor south. At the South Pole every direction is north.

One. The Möbius strip is a surface with only one side and only one boundary component (edge). A line drawn starting from the seam down the middle will meet back at the seam but at the "other side". If continued the line will meet the starting point and will be double the length of the original strip.

By approx 6 meters. For each circle, the length of the circumference is c=2πr. Hence, if a radius grows by 1 meter, the circumference grows by 2 π meters - no matter what the initial value of radius was.

An ellipsoid is a surface that may be obtained from a sphere by deforming it by means of directional scalings, or more generally, of an affine transformation. A rugby ball is an example of ellipsoid.

20,004 km. Continuous travel North must eventually end at the North Pole. So, the maximum distance is half of the Earth's meridional circumference, which can be reached if a plane starts at the South Pole.

4/3π cm3. Equation for the volume of a sphere: 4/3πR^3.

Lemniscate refers not only to the infinity symbol, but also to any geometric shape that is curved like a figure-eight.

Oval biconcave disks. In humans, mature red blood cells are flexible and oval biconcave discs. They lack a cell nucleus and most organelles, in order to accommodate maximum space for hemoglobin; they can be viewed as sacks of hemoglobin, with a plasma membrane as the sack. Approximately 2.4 million new erythrocytes are produced per second in human adults.

In 1777. The letter "i" as a designation of the element from -1 was proposed by Leonhard Euler in 1777. Later, from 1801, this designation was popularized by Carl Friedrich Gauss. Currently, it is the most commonly used symbol of the imaginary unit.

Spiral of Theodorus. In geometry, the spiral of Theodorus is a spiral composed of contiguous right triangles. It was first constructed by Theodorus of Cyrene.The principle of construction is based on the Pythagorean theorem.