Levitation

Levitation

Levitation (from Latin "levitas" "lightness") ["Levitate", "to rise by virtue of lightness," from Latin "levitas" "lightness," patterned in English on "gravitate": [http://dictionary.reference.com/search?q=levitate Online Etymology Dictionary] ] is the process by which an object is suspended against gravity, in a stable position, without physical contact.

It is also a conjuring trick, appearingly raising a human being (or other object) without any physical aid. The illusion can be produced by clever mechanics, lighting arrangements and other means.

Physics

For levitation on Earth, first, a force is required directed vertically upwards and equal to the gravitational force, second, for any small displacement of the levitating object, a returning force should appear to stabilize it. The stable levitation can be naturally achieved by, for example magnetic or aerodynamic forces. With the former, it is essential that diamagnetic elements are used. In this case the returning force appears from the interaction with the screening currents. For example, a superconducting sample, which can be considered either as a perfect diamagnet or an ideally hard superconductor, easily levitates an ambient external magnetic field. In very strong magnetic field, by means of diamagnetic levitation even small live animals have been levitated.

By means of aerodynamic forces, the effect of levitation can also be achieved using the upthrust of air, with the levitating object having the same average density as air.

Scientists have discovered a way of levitating ultra small objects by manipulating the so-called Casimir force, which normally causes objects to stick together by quantum force. This practice however, is only possible for micro-objects. [ [http://news.yahoo.com/s/afp/20070806/sc_afp/britainsciencelevitation_070806132733 Scientists reveal secret of levitation, Yahoo! News] ] [ [http://www.null-hypothesis.co.uk/science/news/item/levitation_magic_nanotechnology_particles_research Levitation in Miniature, Null Hypothesis] ]

Further reading

* esp. the section on levitation in the chapter on electromagnetism.
*.

References

See also

*Types of physical levitation:
**Acoustic levitation
**Aerodynamic levitation
**Electrostatic levitation
**Magnetic levitation
**Optical levitation
*Anti-gravity
*Flying Saints
*Illusions
*Laputa
*Balducci levitation
*Sooperman
*King levitation
*Party Levitation
*Metaphysical levitation
*Weightlessness


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Look at other dictionaries:

  • lévitation — [ levitasjɔ̃ ] n. f. • 1863; angl. levitation, du lat. levitas « légèreté » 1 ♦ Parapsychol. Élévation d objets pesants, spécialt le corps humain, par un procédé psychokinétique. Lévitation d un yogi en état de transe (⇒ léviter) . 2 ♦ Phys.… …   Encyclopédie Universelle

  • Levitation — Lévitation Lévitation de Daniel Dunglas Home (1852) La lévitation est le fait, pour un être ou un objet, de se déplacer ou de rester en suspension au dessus du sol, sous l effet d une force, connue ou inconnue, plus forte que la gravitation. Ce… …   Wikipédia en Français

  • Levitation — bezeichnet Levitation (Parapsychologie), ein parapsychologisches Phänomen, bei dem Menschen und Gegenstände unerklärlich schweben sollen Levitation (Technik), ein technisches Verfahren, bei dem ein Objekt mit Hilfe einer Kraft zum Schweben… …   Deutsch Wikipedia

  • Levitation — Lev i*ta tion ( t[=a] sh[u^]n), n. [L. levis light in weight.] [1913 Webster] 1. Lightness; buoyancy; act of making light. Paley. [1913 Webster] 2. The act or process of making buoyant. [1913 Webster] …   The Collaborative International Dictionary of English

  • levitation — 1660s, noun of action from L. levitas (see LEVITATE (Cf. levitate)) + ION (Cf. ion) …   Etymology dictionary

  • levitation — [lev΄ə tā′shən] n. 1. a levitating or being levitated 2. the illusion of raising and keeping a heavy body in the air with little or no physical support …   English World dictionary

  • levitation — levitational, adj. levitative, adj. /lev i tay sheuhn/, n. 1. the act or phenomenon of levitating. 2. the raising or rising of a body in air by supernatural means. [1660 70; LEVITATE + ION] * * *       rising of a human body off the ground, in… …   Universalium

  • Levitation — levitacija statusas T sritis automatika atitikmenys: angl. levitating; levitation vok. Levitation, f rus. левитация, f pranc. lévitation, f …   Automatikos terminų žodynas

  • levitation — levitacija statusas T sritis automatika atitikmenys: angl. levitating; levitation vok. Levitation, f rus. левитация, f pranc. lévitation, f …   Automatikos terminų žodynas

  • lévitation — levitacija statusas T sritis automatika atitikmenys: angl. levitating; levitation vok. Levitation, f rus. левитация, f pranc. lévitation, f …   Automatikos terminų žodynas

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