physics

Rubik's Snake

Rubik's Snake is a physics topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Rubik's Snake rather than just read about it. In short: A Rubik's Snake (also Rubik's Twist, Rubik's Transformable Snake, Rubik's Snake Puzzle) is a toy with 24 wedges that are right isosceles triangular prisms. The wedges are connected by spring bolts, so that they can be twisted, but not separated.

Key takeaways

Rubik's Snake belongs to physics; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Rubik's Snake to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Rubik's Snake from memory before moving on to harder problems.

Reference excerpt

A Rubik's Snake (also Rubik's Twist, Rubik's Transformable Snake, Rubik's Snake Puzzle) is a toy with 24 wedges that are right isosceles triangular prisms. The wedges are connected by spring bolts, so that they can be twisted, but not separated. By being twisted, the Rubik's Snake can be made to resemble a wide variety of objects, animals, or geometric shapes. Its "ball" shape in its packaging is a non-uniform concave rhombicuboctahedron. The snake was invented by Ernő Rubik, better known as the inventor of the Rubik's Cube. Rubik's Snake was released during 1981 at the height of the Rubik's Cube craze. According to Ernő Rubik: "The snake is not a problem to be solved; it offers infinite possibilities of combination. It is a tool to test out ideas of shape in space. Speaking theoretically, the number of the snake's combinations is limited. But speaking practically, that number is limitless, and a lifetime is not sufficient to realize all of its possibilities." Other manufacturers have produced versions with more pieces than the original.

Structure The 24 prisms are aligned in row with an alternating orientation (normal and upside down). Each prism can adopt 4 different positions, each with an offset of 90°. Usually the prisms have alternating colors.

Notation

Twisting instructions The steps needed to make an arbitrary shape or figure can be described in a number of ways. One common starting configuration is a straight bar with alternating upper and lower prisms, with the rectangular faces facing up and down, and the triangular faces facing towards the player. The 12 lower prisms are numbered 1 through 12 starting from the left, with the left and the right sloping faces of these prisms are labeled L and R respectively. The last of the upper prisms is on the right, so the L face of prism 1 does not have an adjacent prism. The four possible positions of the adjacent prism on each L and R sloping face are numbered 0, 1, 2 and 3 (representing the number of twists between the bottom prism and the L or R adjacent prism). Numbering is based on always twisting the adjacent prism so it swings towards the player: position 1 turns the adjacent blocks towards them, position 2 makes a 90° turn, and position 3 turns the adjacent block away from the player. Position 0 is the starting position, therefore it is not explicitly noted in step-by-step instructions. Using these rules, a twist can be simply described as:

Number of the downward-facing prism (from the left): 1 to 12 Left or right sloping side of the prism: L or R Position of the twist: 1, 2 or 3

Machine processing The position of the 23 turning areas can also be written directly after each other. Here the positions 0, 1, 2 and 3 are always based on the degrees of twist between the right-hand prisms relative to the left-hand prism, when viewed from the right of the axis of rotation. However, this notation is impractical for human readers, because it is difficult to determine the order of the twists.

Fiore method Rather than numbers, Albert Fiore uses letters to refer to the direction the second (rightward) section is turned in relation to the first (leftward) section: D, L, U, and R. These are listed consecutively rather than numbered, so that a completely straight figure rather than being presumed as a starting point is notated DDDDDDDDDDDDDDDDDDDDDDD.

Mathematical formulation The number of different shapes of the Rubik's Snake is at most 423 = 70368744177664 (≈ 7×1013 or 70 trillion), i.e. 23 turning areas with 4 positions each. The real number of different shapes is lower, since some configurations are spatially impossible (because they would require multiple prisms to occupy the same region of space). Peter Aylett computed by an exhaustive search that 13446591920995 (≈ 1.3×1013 or 13 trillion) positions are possible when prohibiting prism collisions, or passing through a collision to reach another position; or 6721828475867 (≈ 6.7×1012) when mirror images (defined as the same sequence of turns, but from the other end of the snake) are counted as the one position, and likewise for rotational symmetries in loops (where the sequence of turns in a loop is cycled).

World record The world record for the "Fastest time to Solve a Snake Rubik's Cube" (into a ball) was set by Lim Kai Yi on 7 January 2024. He completed the puzzle in 2.19 seconds.

See also Combination puzzles Mechanical puzzles Nonplanar flexagons

References

Fiore, Albie (1981). Shaping Rubik's Snake. Penguin Books. ISBN 0-14-006181-9./ISBN 978-0140061819

External links

Rubiks.com Rubiks Snake Fansite, collection of shapes and figures of Rubik's Snake

Illustrations

Worked examples

Example 1 — a first encounter with Rubik's Snake

Start with the simplest possible case. Write down what Rubik's Snake claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In physics, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Rubik's Snake before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Rubik's Snake ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Rubik's Snake

In research: Rubik's Snake appears in physics research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Rubik's Snake in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Rubik's Snake is common in secondary-school and first-year university syllabi. It links to neighbouring topics 1980s toys, Combination puzzles, Hungarian inventions, so understanding it makes those chapters shorter.
In everyday life: Look for Rubik's Snake outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

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How to study Rubik's Snake in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Rubik's Snake means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Rubik's Snake out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Rubik's Snake in simple terms?

Why does Rubik's Snake matter?

Because it connects several physics ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Rubik's Snake?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Rubik's Snake.