A spinning top, or simply a top, is a toy with a squat body and a sharp point at the bottom, designed to be rotation on its vertical axis, balancing on the tip due to the gyroscopic effect.
Once set in motion, a top will usually precession for a few seconds, spin upright for a while, then start to wobble again with increasing amplitude as it loses energy, and finally tip over and roll on its side.
Tops exist in many variations and materials, chiefly wood, metal, and plastic, often with a metal tip. They may be set in motion by twirling a handle with the fingers, by pulling a rope coiled around the body, or through a built-in auger (spiral plunger).
Such toys have been used since antiquity in solitary or competitive , where each player tries to keep one's top spinning for as long as possible or achieve some other goal. Some tops have faceted bodies with symbols or inscriptions, and are used like dice to inject randomness into games or for divination and ritual purposes.
The ubiquity of spinning tops lends to the fact that the toy is used to name many living things such as Cyclosa turbinata, whose name comes from the Latin roots for spinning top.
Besides toys, tops have also historically been used for gambling and prophecy. Some role-playing games use tops to augment dice in generating randomized results; it is in this case referred to as a spinner.
Gould mentions maple seeds, celts (leading to ), the bow drill, the spindle whorl, and the potter's wheel as possible predecessors to the top, which he assumes was invented or discovered multiple times in multiple places.
Maxwell took this a step further by using a circular scale around the rim with which to measure the ratios of the primaries, choosing vermilion, emerald, and ultramarine.
These tops may be thrown forward while firmly grasping the end of the string and pulling it back. The forward momentum of the top contributes to the string's tension and thus to the final spin rate.
In some throwing styles, the top is thrown upside-down, but the first loop of the rope is wound around a stubby "head". Then, the sudden yank on the head as the string finishes unwinding causes the spinning top to flip over and land on its tip.
Alternatively, tops of this class may be started by hand but then accelerated and kept in motion by striking them repeatedly with a small whip.
Because of the small contact area between the tip and the underlying surface, and the large rotational inertia of its body, a top that is started on a hard surface will usually keep spinning for tens of seconds or more, even without additional energy input.
Typically the top will at first wobble until friction and torque between the tip and the underlying surface force it to spin with the axis steady and upright. Contrary to what is sometimes assumed, longstanding scientific studies (and easy experimentations reproducible by anyone) show that reducing the friction increases the time needed to reach this stable state (unless the top is so unbalanced that it falls over before reaching it).
The total spinning time of a top is generally increased by increasing its moment of inertia and lowering its center of gravity. These variables however are constrained by the need to prevent the body from touching the ground.
Asymmetric tops of virtually any shape can also be created and designed to balance.
An exhaustive description of the mathematics and physics of the top can be found in the four volume monograph of Felix Klein et al.
The Top is a short story by Czech literature writer Franz Kafka.Kafka, Franz. The Complete Stories. New York City: Schocken Books, 1995.
Rock band The Cure released The Top album in 1984, named, and at least partially inspired, by the toy of the same name. The album includes the title track in which the sound of a spinning top can be heard at the beginning of the song.
The top is a focal element and metaphysical symbol in the movie Inception (2010), directed by Christopher Nolan and starring Leonardo DiCaprio. In the final shot, the camera moves over the spinning top just before it appears to be wobbling.
In 2022, an Armenian culture spinning top, with the song "Spin the Magic", was chosen as the theme art and the main motif for the 20th edition of Junior Eurovision Song Contest, which will be held in Yerevan, Armenia.
Color demonstrations with tops
Spinning methods
Finger twirling
Strings and whips
Augers
Magnetic fields
Notable types
Modern tops have several sophisticated improvements, such as ball bearings of ruby or a hard ceramic like tungsten carbide, that reduces the friction with the ground surface. Functional art tops have become collectibles built using varied techniques in metal-working, glass-working, and wood-working.
Physics
Competitions
In popular culture
See also
Further reading
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