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compare spiral angles

CRcrkcity•Created April 18, 2021
compare spiral angles
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Instructions

Choose angle and click flag. Altering number of colors highlights different spiral patterns. Hit space key to freeze. 30 degrees is 1/12th of a turn, so 12 arms result. 36 degress is 1/10th a turn, so 10 arms result. 51.43... degrees is 1/7th a turn, so 7 arms result. Lots of space between those arms. Is there any angle that fills the space? The golden angle does. Each new floret turns 137.5 degrees, the angle that best fills the space. Count the numer of clockwise spirals and count the counterclockwise spirals. Each will be a Fibonacci number. Each new floret shows it's birth order, 1, 2,3... If you subtract successive numbers in a spiral you will find Fibonacci numbers (such as 13, 21, 34, 55, 89...).

Description

The colors help you see many different spiral patterns, some clockwise, others counterclockwise. You can create hybrid patterns by changing the number of colors every few seconds. Uses clones that move out from the center. If you choose the golden angle, each successive clone moves at the golden angle (137.5 degrees) relative to the previously created clone. Each clone represents a floret that starts from the center, then migrates outwards, growing slightly as it moves. The golden angle turn of 137.5 degrees is the best way to fill space, and causes the number of clockwise and counterclockwise spirals to be Fibonacci numbers (such as 5, 8, 13, 21, 34, 55, 89, 144....). Altering number of colors highlights different spiral patterns. Had to make costumes for numbers, but only made costumes for up to 102 numbers. After that number, the cycle repeats. (the code kills off clones once they are far from center. This allows us to bypass the clone number limit in Scratch, so we can continuously create new clones) Sunflowers, daisies and other flowers have this type of spiral patterns. We produced the very similar programs in Python and NetLogo to provide a comparison: https://lifepatternsemerging.com/spirals See also our Scratch model using a pen rather than moving clones.

Project Details

Project ID517473742
CreatedApril 18, 2021
Last ModifiedApril 19, 2021
SharedApril 19, 2021
Visibilityvisible
CommentsAllowed