Euler's Disk

Euler's Disk, invented between 1987 and 1990 by Joseph Bendik, is a trademarked scientific educational toy. It is used to illustrate and study the dynamic system of a spinning and rolling disk on a flat or curved surface

Joseph Bendik first noted the interesting motion of the spinning disk while working at Hughes Aircraft (Carlsbad Research Center) after spinning a heavy polishing chuck on his desk at lunch one day. The apparatus is a dramatic visualization of energy exchanges in three different, tightly coupled processes. As the disk gradually decreases its azimuthal rotation, there is also a decrease in amplitude and increase in the frequency of the disk's axial precession.[4] The evolution of the disk's axial precession is easily visualized in a slow motion video by looking at the side of the disk following a single point marked on the disk. The evolution of the rotation of the disk is easily visualized in slow motion by looking at the top of the disk following an arrow drawn on the disk representing its radius. As the disk releases the initial energy given by the user and approaches a halt, its rotation about the vertical axis slows, while its contact point oscillation increases. Lit from above, its contact point and nearby lower edge in shadow, the disk appears to levitate before halting. Bendik named the toy after mathematician Leonhard Euler. The commercial toy consists of a heavy, thick chrome-plated steel disk and a rigid, slightly concave, mirrored base. Included holographic magnetic stickers can be attached to the disk, to enhance the visual effect of wobbling. These attachments may make it harder to see and understand the processes at work, however. When spun on a flat surface, the disk exhibits a spinning/rolling motion, slowly progressing through varying rates and types of motion before coming to rest. Most notably, the precession rate of the disk's axis of symmetry increases as the disk spins down. The mirror base provides a low-friction surface; its slight concavity keeps the disk from "wandering" off the surface. Any disk, spun on a reasonably flat surface (such as a coin spun on a table), will exhibit essentially the same type of motion as an Euler Disk, but for a much shorter time. Commercial disks provide a more effective demonstration of the phenomenon, having an optimized aspect ratio and a precision polished, slightly rounded edge to maximize the spinning/rolling time.

Girls vs Boys

The following symbols and notations were introduced by Leohard Euler

Woah, this is like the hypnotic spin of the universe condensed down to a tabletop. 🌀 Physics is the real magic show, folks. Watch this Euler's Disk blur the line between science and sorcery! 🧙‍♂️✨ Mind officially blown! 🤯 Don't wanna miss this one

Euler's disk, also known as the Spinning Coin, is a scientific toy invented by the Swiss mathematician Leonhard Euler. As the disk spins, it produces a mesmerising pattern of colours and sounds.

What one horse power can do 😳

Euler's disk. 117 seconds oddly satisfying video. 😵‍💫

Remind you of Inception?