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Thursday, September 23, 2021

09-23-2021-0606 - Archimedean spiral

 The Archimedean spiral (also known as the arithmetic spiral) is a spiral named after the 3rd-century BC Greek mathematician Archimedes. It is the locus corresponding to the locations over time of a point moving away from a fixed point with a constant speed along a line that rotates with constant angular velocity. Equivalently, in polar coordinates (rθ) it can be described by the equation

with real numbers a and b. Changing the parameter a moves the centerpoint of the spiral outward from the origin (positive a toward Î¸ = 0 and negative a toward Î¸ = Ï€) essentially through a rotation of the spiral, while b controls the distance between loops.

From the above equation, it can thus be stated: the position of particle from the point of start is proportional to the angle Î¸ as time elapses.

Archimedes described such a spiral in his book On Spirals.  Conon of Samos was a friend of his and Pappusstates that this spiral was discovered by Conon.[1]

Three 360° loops of one arm of an Archimedean spiral

https://en.wikipedia.org/wiki/Archimedean_spiral

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