Top

A top is a toy designed to be spun rapidly on the ground, the motion of which causes it to remain precisely balanced on its tip because of inertia. Such toys have existed since antiquity. Traditionally tops were constructed of wood, sometimes with an iron tip, and would be set in motion by aid of a string or rope coiled around its axis which, when pulled quickly, caused a rapid unwinding that would set the top in motion. Today they are often built of plastic, and modern materials and manufacturing processes allow tops to be constructed with such precise balance that they can be set in motion by a simple twist of the fingers and twirl of the wrist without need for string or rope.

Characteristics

The motion of a top is produced in the most simple forms by twirling the stem using the fingers. More sophisticated tops are spun by holding the axis firmly while pulling a string or twisting a stick or pushing an auger. In the kinds with an auger, an internal weight rotates, producing an overall circular motion. Some tops can be thrown, while firmly grasping a string that had been tightly wound around the stem, and the centrifugal force generated by the unwinding motion of the string will set them spinning upon touching ground.

Top (mathematics)

In the context of a module M over a ring R, the top of M is the largest semisimple quotient module of M if it exists.

For finite-dimensional k-algebras (k a field), if rad(M) denotes the intersection of all proper maximal submodules of M (the radical of the module), then the top of M is M/rad(M). In the case of local rings with maximal ideal P, the top of M is M/PM. In general if R is a semilocal ring (=semi-artinian ring), that is, if R/Rad(R) is an Artinian ring, where Rad(R) is the Jacobson radical of R, then M/rad(M) is a semisimple module and is the top of M. This includes the cases of local rings and finite dimensional algebras over fields.

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Top (clothing)

A top is clothing that covers at least the chest, but which usually covers most of the upper human body between the neck and the waistline. The bottom of tops can be as short as mid-torso, or as long as mid-thigh. Men's tops are generally paired with pants, and women's with pants or skirts. Common types of tops are t-shirts, blouses and shirts.

Design

The neckline is the highest line of the top, and may be as high as a head-covering hood, or as low as the waistline or bottom hem of the top. A top may be worn loose or tight around the bust or waist, and may have sleeves or shoulder straps, spaghetti straps (noodle straps), or may be strapless. The back may be covered or bare. Tops may have straps around the waist or neck, or over the shoulders.

Types

Neck styles

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Experiment

An experiment is a procedure carried out to verify, refute, or validate a hypothesis. Experiments provide insight into cause-and-effect by demonstrating what outcome occurs when a particular factor is manipulated. Experiments vary greatly in goal and scale, but always rely on repeatable procedure and logical analysis of the results. There also exist natural experimental studies.

A child may carry out basic experiments to understand gravity, while teams of scientists may take years of systematic investigation to advance their understanding of a phenomenon. Experiments and other types of hands-on activities are very important to student learning in the science classroom. Experiments can raise test scores and help a student become more engaged and interested in the material they are learning, especially when used over time. Experiments can vary from personal and informal natural comparisons (e.g. tasting a range of chocolates to find a favorite), to highly controlled (e.g. tests requiring complex apparatus overseen by many scientists that hope to discover information about subatomic particles). Uses of experiments vary considerably between the natural and human sciences.

Experiment (locomotive)

Experiment was a steam locomotive designed and built by Richard Roberts in 1833 for the Liverpool and Manchester Railway (L&MR). The locomotive had vertical cylinders driving via bell cranks.

History

L&MR No.32Experiment was built in 1833 with vertical cylinders mounted just behind the chimney, driving the wheels via a bell crank. The locomotive also had piston valves. These valves were probably the reason that the design was not a success, rather than the bell crank transmission, which was used successfully in other locomotives. Another reason that the locomotive was not successful was steam leakage from the cylinders. Experiment was withdrawn after a few months.

Three similar locomotives were built for the Dublin and Kingstown Railway. Locomotives to this design were built for the Dundee and Newtyle Railway, but they were soon altered.

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Experiment (1988 film)

Eksperiment (Russian: Эксперимент, lit. Experiment) is a 1988 Soyuzmultfilm's satirical animated film about the bureaucrats directed by Yefim Gamburg and written by Michail Gurevich and Olgert Libkin. It was created in traditional hand-drawn animation technique.

Plot

Experiment is set in a town, where the citizens were forced walk everywhere by foot because of constant traffic jams. To solve this situation, city officials decided to conduct an experiment: people were allowed to fly. Most citizens immediately grew wings and quickly moved to a new lifestyle, however, for some reason wings did not grow on few others. To find such wingless people a place for life, they decided to appoint flight supervisors and invented strict rules and regulations for the flights.

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