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887:(in other words, in a U-shape). The permanent kind has become the most widely recognized symbol for magnets. It is usually depicted as red and marked with 'North' and 'South' poles. Although rendered obsolete in the 1950s by squat, cylindrical magnets made of modern materials, horseshoe magnets are still regularly shown in elementary school textbooks. Historically, they were a solution to the problem of making a compact magnet that does not destroy itself in its own demagnetizing field.
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The shape of the magnet was originally created as a replacement for the bar magnet as it makes the magnetic field stronger for a magnet of comparable strength. A horseshoe magnet is stronger because both poles of the magnet are closer to each other and in the same plane which allows the magnetic
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922:. Sturgeon showed that he could regulate the magnetic field of his horseshoe magnet by increasing or decreasing the amount of current being run through the wires. This would lay the groundwork for development of the
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This was also the first practical electromagnet and the first magnet that could lift more mass than the magnet itself when the seven-ounce magnet was able to lift nine pounds of
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Horseshoe magnet with computed magnetic field lines. The two magnetic poles are in close vicinity, which concentrates the field lines and creates a strong magnetic field.
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substance instead of air. The nearness of the horseshoe magnetâs poles facilitates the ability to use these magnet keepers more easily than other types of magnets.
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also known as the "staying magnetized" ability of a given magnet. Coercivity is weaker in disc or ring shapes, slightly stronger in
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are used. A magnetic field holds its strength best when the entire magnetic field is given the ability to loop through a
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This article is about objects and devices that produce magnetic fields. For a description of magnetic materials, see
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or bar shapes, and strongest in horseshoe shapes. To increase the coercivity of horseshoe magnets, steel keepers or
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Magnetic field of a horseshoe magnet. The field is greatest where the lines are densest, around the poles (lower)
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The shape of the horseshoe magnet also drastically reduces its demagnetization over time. This is due to
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piece of iron and running electric current through the wires creating the first horseshoe magnet.
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to flow along a more direct path between the poles and concentrates the magnetic field.
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were attempted. These experiments culminated in
William Sturgeon wrapping wire around a
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Assortment of AlNiCo horseshoe magnet shapes available from a manufacturer in 1956.
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needle. Following this discovery, many other experiments surrounding
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Magnetic fields of a horseshoe magnet visualized using iron filings.
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tube in an early microwave oven. About 3 in (8 cm) long.
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1158:"William Sturgeon and the Invention of the Electromagnet"
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1183:"The Various Shapes of Magnets and Their Uses"
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1244:"Why are Magnets Shaped like Horseshoes?"
1090:"Why are Magnets Shaped like Horseshoes?"
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895:In 1819, it was discovered that passing
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590:Electromagnetism and special relativity
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1100:from the original on 24 December 2022
610:Maxwell equations in curved spacetime
1131:SPARK Museum of Electrical Invention
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1211:"Temperature and Neodymium Magnets"
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13:
1002:Alnico horseshoe magnet used in a
16:Magnet in the shape of a horseshoe
14:
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1156:Bellis, Mary (23 February 2019).
1123:"Magnetism and Electromagnetism"
1061:Magnetism and Magnetic Materials
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1030:A rectangular horseshoe magnet.
930:for the next century and more.
1:
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926:and the future of world-wide
615:Relativistic electromagnetism
1404:ferromagnetic superconductor
1273:"Demagnetizing a Steel Nail"
7:
974:A horseshoe magnet made of
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1066:Cambridge University Press
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340:LiĂ©nardâWiechert potential
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605:Mathematical descriptions
315:Electromagnetic radiation
305:Electromagnetic induction
245:Magnetic vector potential
240:Magnetic scalar potential
1250:. K&J Magnetics, Inc
1217:. K&J Magnetics, Inc
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1361:Van Vleck paramagnetism
1058:Coey, J. M. D. (2010).
883:made in the shape of a
155:Electrostatic induction
150:Electrostatic discharge
25:Magnet (disambiguation)
1094:K&J Magnetics, Inc
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585:Electromagnetic tensor
23:. For other uses, see
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578:Covariant formulation
370:Synchrotron radiation
310:Electromagnetic pulse
300:Electromagnetic field
924:electrical telegraph
620:Stressâenergy tensor
545:Reluctance (complex)
290:Displacement current
1431:amorphous magnetism
1399:superferromagnetism
899:through a piece of
535:Magnetomotive force
420:Electromotive force
390:Alternating current
325:Jefimenko equations
285:Cyclotron radiation
1384:antiferromagnetism
1356:superparamagnetism
928:telecommunications
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383:Electrical network
220:Gauss magnetic law
185:Static electricity
145:Electric potential
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1344:superdiamagnetism
1332:Magnetic response
1248:K&J Magnetics
1215:K&J Magnetics
1075:978-0-511-67743-4
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550:Reluctance (real)
520:Gyratorâcapacitor
465:Resonant cavities
355:Maxwell equations
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873:horseshoe magnet
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510:Electric machine
493:Magnetic circuit
455:Parallel circuit
445:Network analysis
410:Electric current
345:London equations
190:Triboelectricity
180:Potential energy
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39:Electromagnetism
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400:Current density
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273:Electrodynamics
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77:Computational
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1339:diamagnetism
1280:. Retrieved
1276:
1252:. Retrieved
1247:
1219:. Retrieved
1214:
1190:. Retrieved
1187:Apex Magnets
1186:
1177:
1165:. Retrieved
1161:
1134:. Retrieved
1127:Spark Museum
1126:
1102:. Retrieved
1093:
1084:
1060:
945:
937:
917:
903:deflected a
894:
875:is either a
872:
870:
852:
595:Four-current
530:Linear motor
415:Electrolysis
295:Eddy current
255:Permeability
175:Polarization
170:Permittivity
1104:23 February
565:Transformer
395:Capacitance
320:Faraday law
115:Coulomb law
57:Electricity
1426:spin glass
1036:References
948:coercivity
632:Scientists
480:Waveguides
460:Resistance
430:Inductance
210:AmpĂšre law
1325:Magnetism
1282:3 January
1277:Sciencing
1254:3 January
1221:3 January
1192:3 January
1167:3 January
1162:ThoughtCo
1136:3 January
1004:magnetron
939:lines of
909:magnetism
885:horseshoe
877:permanent
788:Steinmetz
718:Kirchhoff
703:Jefimenko
698:Hopkinson
683:Helmholtz
678:Heaviside
540:Permeance
425:Impedance
165:Insulator
160:Gauss law
110:Conductor
87:Phenomena
82:Textbooks
62:Magnetism
21:Magnetism
1453:Category
1436:spin ice
1098:Archived
952:cylinder
813:Wiechert
768:Poynting
658:Einstein
505:DC motor
500:AC motor
335:Lenz law
120:Electret
905:compass
891:History
798:Thomson
773:Ritchie
763:Poisson
748:Neumann
743:Maxwell
738:Lorentz
733:Liénard
663:Faraday
648:Coulomb
475:Voltage
450:Ohm law
72:History
1072:
976:AlNiCo
783:Singer
778:Savart
758:Ărsted
723:Larmor
713:Kelvin
668:Fizeau
638:AmpĂšre
560:Stator
67:Optics
934:Shape
901:metal
808:Weber
803:Volta
793:Tesla
708:Joule
693:Hertz
688:Henry
673:Gauss
555:Rotor
1284:2021
1256:2021
1223:2021
1194:2021
1169:2021
1138:2021
1106:2023
1070:ISBN
941:flux
920:iron
728:Lenz
653:Davy
643:Biot
753:Ohm
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Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
