SlideShare une entreprise Scribd logo
1  sur  3
A Brief History
The history of magnets is shrouded in mystery and legend.
Ancient History
The most popular account for the discovery of magnets is a
legend of a shepherd named Magnes who lived in Magnesia near
Mount Ida in Greece Mount Ida was referred to as the "Mountain
of the Goddess". Approximately 2,600 years ago (600 BC) while
herding sheep on the mountain, Magnes found that the nails and
buckle of his sandals and the tip of his staff were attracted to the
rock he was standing on. He dug up the Earth to find lodestones.
Lodestones contain magnetite, a natural magnetic material
Fe3O4.
The word magnet is derived from the Greek name magnetis
lithos, the stone of Magnesia, referring to the region on the
Aegean coast in present-day Turkey where these magnetic stones
were found.
Middle Ages History
The Chinese provide the first documented use of suspended
lodestones used as a compass. In 1088 Shen Kuo described the
magnetic needle compass, which could be used for navigation in
his Dream Pool Essays. The first recorded use was documented
by Zheng He of the Yunnan province. Between the years 1405
and 1433, Zheng He recorded his voyages across seven oceans.
In approximately 1180, Englishman Alexander Neckam records
the earliest European understanding of the magnet as a guide to
seamen, the early compass. The term lodestone comes from the
Anglo-Saxon meaning "leading stone," or literally, "the stone that
leads." The Icelandic word is leider-stein, and was used in
writings of that period in reference to the navigation of ships.
Modern History
In 1600, English scientist William Gilbert confirmed earlier
observations regarding magnetic poles and concluded that the
Earth was a magnet. In 1820, the Dutch scientist Hans Christian
Oersted discovered the relationship between electricity and
magnetism, and French physicist Andre Ampere further expanded
upon this discovery in 1821.
In the early 1900s, scientists began studying magnetic materials
other than those based on iron and steel. By the 1930s,
researchers had produced the first powerful Alnico alloy
permanent magnets.
In 1966 the first rare earth magnets were developed from
Samarium-Cobalt (SmCo5) producing a high energy product of 18
MGOe. In 1972 further developments were made using
Samarium-Cobalt (Sm2Co17) to produce a higher energy magnet
product of 30 MGOe.
In 1983 General Motors, Sumitomo Special Metals and the
Chinese Academy of Sciences developed a high energy product of
35 MGOe from a compound of Neodymium-Iron-Boron
(Nd2Fe14B) referred to as neo magnets or rare earth magnets.
The enormous interest these magnets have generated arises
because, for the first time, a new magnetic material has been
introduced which is not only stronger than the previous
generation but is more efficient. Neo magnets are the strongest
type of permanent magnet in the world.
Today magnets play a role almost every technologically advanced
device we use, including computers, automobiles, industrial sorter
and seperators, power generators, speakers, cell phones etc.

Contenu connexe

Tendances

Galileo
GalileoGalileo
GalileoSajib
 
famous scientist.pdf
famous scientist.pdffamous scientist.pdf
famous scientist.pdfSharan49198
 
HEATING EFFECT OF CURRENT
HEATING EFFECT OF CURRENTHEATING EFFECT OF CURRENT
HEATING EFFECT OF CURRENTSheeba vinilan
 
Electric current and its effects
Electric current and its effectsElectric current and its effects
Electric current and its effectsagarwalabhi
 
Presentation on Electric Circuits
Presentation on Electric Circuits Presentation on Electric Circuits
Presentation on Electric Circuits MuhammadIb1
 
Aryabhatta life story
Aryabhatta life story Aryabhatta life story
Aryabhatta life story Akshat Kumar
 
Presentation on electric circuit
Presentation on electric circuit Presentation on electric circuit
Presentation on electric circuit topu93
 
Albert einstein jan2012 final
Albert einstein jan2012 finalAlbert einstein jan2012 final
Albert einstein jan2012 finalGTClub
 
Electromagnetic induction
Electromagnetic inductionElectromagnetic induction
Electromagnetic inductionAKRAM HABIB
 
Static electricity
Static electricityStatic electricity
Static electricityVIGYANPRASAR
 
Great Indian Mathematicians
Great Indian MathematiciansGreat Indian Mathematicians
Great Indian MathematiciansShobha Hassan
 
Electromagnetic induction
Electromagnetic inductionElectromagnetic induction
Electromagnetic inductionAsuquo Asuquo
 
Galileo galilei
Galileo galileiGalileo galilei
Galileo galileiHaneefz
 
Indian Mathematicians And Their Contribution
Indian Mathematicians And Their ContributionIndian Mathematicians And Their Contribution
Indian Mathematicians And Their Contributiondivyanshsngh
 

Tendances (20)

Galileo
GalileoGalileo
Galileo
 
famous scientist.pdf
famous scientist.pdffamous scientist.pdf
famous scientist.pdf
 
HEATING EFFECT OF CURRENT
HEATING EFFECT OF CURRENTHEATING EFFECT OF CURRENT
HEATING EFFECT OF CURRENT
 
Electric current and its effects
Electric current and its effectsElectric current and its effects
Electric current and its effects
 
Presentation on Electric Circuits
Presentation on Electric Circuits Presentation on Electric Circuits
Presentation on Electric Circuits
 
Aryabhatta life story
Aryabhatta life story Aryabhatta life story
Aryabhatta life story
 
Scientists
ScientistsScientists
Scientists
 
Presentation on electric circuit
Presentation on electric circuit Presentation on electric circuit
Presentation on electric circuit
 
Albert einstein jan2012 final
Albert einstein jan2012 finalAlbert einstein jan2012 final
Albert einstein jan2012 final
 
Aryabhata-An Indian Mathemagician
 Aryabhata-An Indian Mathemagician Aryabhata-An Indian Mathemagician
Aryabhata-An Indian Mathemagician
 
Electromagnetic induction
Electromagnetic inductionElectromagnetic induction
Electromagnetic induction
 
Electrostatics -1
Electrostatics -1Electrostatics -1
Electrostatics -1
 
Static electricity
Static electricityStatic electricity
Static electricity
 
Magnetism
MagnetismMagnetism
Magnetism
 
Great Indian Mathematicians
Great Indian MathematiciansGreat Indian Mathematicians
Great Indian Mathematicians
 
MATHEMATICIANS
MATHEMATICIANSMATHEMATICIANS
MATHEMATICIANS
 
Electromagnetic induction
Electromagnetic inductionElectromagnetic induction
Electromagnetic induction
 
Galileo galilei
Galileo galileiGalileo galilei
Galileo galilei
 
Indian Mathematicians And Their Contribution
Indian Mathematicians And Their ContributionIndian Mathematicians And Their Contribution
Indian Mathematicians And Their Contribution
 
Pendulum
PendulumPendulum
Pendulum
 

En vedette

Pic analysis essay
Pic analysis essayPic analysis essay
Pic analysis essaynichols148
 
Apoorva Javadekar - Conditional Correlations of Macro Variables and Implica...
 Apoorva Javadekar - Conditional Correlations of Macro Variables and  Implica... Apoorva Javadekar - Conditional Correlations of Macro Variables and  Implica...
Apoorva Javadekar - Conditional Correlations of Macro Variables and Implica...Apoorva Javadekar
 
Evaluacion formativa de musica
Evaluacion formativa de musicaEvaluacion formativa de musica
Evaluacion formativa de musicapedro nunez
 
Looma_HMI(executive)_content WxH
Looma_HMI(executive)_content WxHLooma_HMI(executive)_content WxH
Looma_HMI(executive)_content WxHWei (Vicky) Guo
 
YouTube - Apresentação
YouTube - ApresentaçãoYouTube - Apresentação
YouTube - ApresentaçãoHéber Cruz
 
Flowers ( lavender , chamomile & Hibiscus)
Flowers ( lavender , chamomile & Hibiscus)Flowers ( lavender , chamomile & Hibiscus)
Flowers ( lavender , chamomile & Hibiscus)Mahmoud M. Sallam
 

En vedette (10)

Pic analysis essay
Pic analysis essayPic analysis essay
Pic analysis essay
 
Apoorva Javadekar - Conditional Correlations of Macro Variables and Implica...
 Apoorva Javadekar - Conditional Correlations of Macro Variables and  Implica... Apoorva Javadekar - Conditional Correlations of Macro Variables and  Implica...
Apoorva Javadekar - Conditional Correlations of Macro Variables and Implica...
 
Evaluacion formativa de musica
Evaluacion formativa de musicaEvaluacion formativa de musica
Evaluacion formativa de musica
 
desmon upd cv
desmon upd cvdesmon upd cv
desmon upd cv
 
Looma_HMI(executive)_content WxH
Looma_HMI(executive)_content WxHLooma_HMI(executive)_content WxH
Looma_HMI(executive)_content WxH
 
DTS_4148-grandmaster
DTS_4148-grandmasterDTS_4148-grandmaster
DTS_4148-grandmaster
 
Summit2015
Summit2015Summit2015
Summit2015
 
YouTube - Apresentação
YouTube - ApresentaçãoYouTube - Apresentação
YouTube - Apresentação
 
ResumeB
ResumeBResumeB
ResumeB
 
Flowers ( lavender , chamomile & Hibiscus)
Flowers ( lavender , chamomile & Hibiscus)Flowers ( lavender , chamomile & Hibiscus)
Flowers ( lavender , chamomile & Hibiscus)
 

Similaire à A brief history on magnets

Basics and history
Basics and historyBasics and history
Basics and historyRama Kumar
 
p080-p083 Knoch EarthsMagneticField
p080-p083 Knoch EarthsMagneticFieldp080-p083 Knoch EarthsMagneticField
p080-p083 Knoch EarthsMagneticFieldJaime Knoch
 
Earth's magnetism
Earth's magnetismEarth's magnetism
Earth's magnetismRacy Rafols
 
Earthsmagnetism 120427184625-phpapp01
Earthsmagnetism 120427184625-phpapp01Earthsmagnetism 120427184625-phpapp01
Earthsmagnetism 120427184625-phpapp01prajwalsharma24
 
£££ Jack Oughton - Planetary Science Presentation 03 - A Brief Guide To Terre...
£££ Jack Oughton - Planetary Science Presentation 03 - A Brief Guide To Terre...£££ Jack Oughton - Planetary Science Presentation 03 - A Brief Guide To Terre...
£££ Jack Oughton - Planetary Science Presentation 03 - A Brief Guide To Terre...Jack Oughton
 
Proyecto sìntesis
Proyecto sìntesisProyecto sìntesis
Proyecto sìntesisyangie25
 
Geology of an amber locality in the hukawng valley northern myanmar
Geology of an amber locality in the hukawng valley northern myanmarGeology of an amber locality in the hukawng valley northern myanmar
Geology of an amber locality in the hukawng valley northern myanmarYMCA Mandalay
 
International day of the asteroid
International day of the asteroidInternational day of the asteroid
International day of the asteroidParlamento Asgardia
 
International day of the asteroid
International day of the asteroidInternational day of the asteroid
International day of the asteroidParlamento Asgardia
 
Stonehenge
StonehengeStonehenge
StonehengeHome
 
The earth’s interior
The earth’s interiorThe earth’s interior
The earth’s interiorjnr
 
Magnetism- Homer
Magnetism- HomerMagnetism- Homer
Magnetism- HomerDavanz87
 
Timeline of Magnetism.pptx
Timeline of Magnetism.pptxTimeline of Magnetism.pptx
Timeline of Magnetism.pptxWawaKrishna
 
Chinese inventionsgr4 final
Chinese inventionsgr4 finalChinese inventionsgr4 final
Chinese inventionsgr4 finallindylorman
 
Transits of Venus and modern astronomy in India
Transits of Venus and modern  astronomy in IndiaTransits of Venus and modern  astronomy in India
Transits of Venus and modern astronomy in IndiaRajesh Kochhar
 
Physics Holi
Physics HoliPhysics Holi
Physics Holirockstarr
 

Similaire à A brief history on magnets (20)

Earth's magnetism
Earth's magnetismEarth's magnetism
Earth's magnetism
 
Basics and history
Basics and historyBasics and history
Basics and history
 
p080-p083 Knoch EarthsMagneticField
p080-p083 Knoch EarthsMagneticFieldp080-p083 Knoch EarthsMagneticField
p080-p083 Knoch EarthsMagneticField
 
Magnatism final paper
Magnatism final paperMagnatism final paper
Magnatism final paper
 
Earth's magnetism
Earth's magnetismEarth's magnetism
Earth's magnetism
 
Earthsmagnetism 120427184625-phpapp01
Earthsmagnetism 120427184625-phpapp01Earthsmagnetism 120427184625-phpapp01
Earthsmagnetism 120427184625-phpapp01
 
£££ Jack Oughton - Planetary Science Presentation 03 - A Brief Guide To Terre...
£££ Jack Oughton - Planetary Science Presentation 03 - A Brief Guide To Terre...£££ Jack Oughton - Planetary Science Presentation 03 - A Brief Guide To Terre...
£££ Jack Oughton - Planetary Science Presentation 03 - A Brief Guide To Terre...
 
Proyecto sìntesis
Proyecto sìntesisProyecto sìntesis
Proyecto sìntesis
 
Geology of an amber locality in the hukawng valley northern myanmar
Geology of an amber locality in the hukawng valley northern myanmarGeology of an amber locality in the hukawng valley northern myanmar
Geology of an amber locality in the hukawng valley northern myanmar
 
2. Continental Drift.pptx
2. Continental Drift.pptx2. Continental Drift.pptx
2. Continental Drift.pptx
 
International day of the asteroid
International day of the asteroidInternational day of the asteroid
International day of the asteroid
 
International day of the asteroid
International day of the asteroidInternational day of the asteroid
International day of the asteroid
 
Stonehenge
StonehengeStonehenge
Stonehenge
 
The earth’s interior
The earth’s interiorThe earth’s interior
The earth’s interior
 
Quiztronomy 13 finals
Quiztronomy 13 finalsQuiztronomy 13 finals
Quiztronomy 13 finals
 
Magnetism- Homer
Magnetism- HomerMagnetism- Homer
Magnetism- Homer
 
Timeline of Magnetism.pptx
Timeline of Magnetism.pptxTimeline of Magnetism.pptx
Timeline of Magnetism.pptx
 
Chinese inventionsgr4 final
Chinese inventionsgr4 finalChinese inventionsgr4 final
Chinese inventionsgr4 final
 
Transits of Venus and modern astronomy in India
Transits of Venus and modern  astronomy in IndiaTransits of Venus and modern  astronomy in India
Transits of Venus and modern astronomy in India
 
Physics Holi
Physics HoliPhysics Holi
Physics Holi
 

Dernier

The Mariana Trench remarkable geological features on Earth.pptx
The Mariana Trench remarkable geological features on Earth.pptxThe Mariana Trench remarkable geological features on Earth.pptx
The Mariana Trench remarkable geological features on Earth.pptxseri bangash
 
Stages in the normal growth curve
Stages in the normal growth curveStages in the normal growth curve
Stages in the normal growth curveAreesha Ahmad
 
module for grade 9 for distance learning
module for grade 9 for distance learningmodule for grade 9 for distance learning
module for grade 9 for distance learninglevieagacer
 
Introduction of DNA analysis in Forensic's .pptx
Introduction of DNA analysis in Forensic's .pptxIntroduction of DNA analysis in Forensic's .pptx
Introduction of DNA analysis in Forensic's .pptxrohankumarsinghrore1
 
Zoology 5th semester notes( Sumit_yadav).pdf
Zoology 5th semester notes( Sumit_yadav).pdfZoology 5th semester notes( Sumit_yadav).pdf
Zoology 5th semester notes( Sumit_yadav).pdfSumit Kumar yadav
 
Pulmonary drug delivery system M.pharm -2nd sem P'ceutics
Pulmonary drug delivery system M.pharm -2nd sem P'ceuticsPulmonary drug delivery system M.pharm -2nd sem P'ceutics
Pulmonary drug delivery system M.pharm -2nd sem P'ceuticssakshisoni2385
 
Velocity and Acceleration PowerPoint.ppt
Velocity and Acceleration PowerPoint.pptVelocity and Acceleration PowerPoint.ppt
Velocity and Acceleration PowerPoint.pptRakeshMohan42
 
Asymmetry in the atmosphere of the ultra-hot Jupiter WASP-76 b
Asymmetry in the atmosphere of the ultra-hot Jupiter WASP-76 bAsymmetry in the atmosphere of the ultra-hot Jupiter WASP-76 b
Asymmetry in the atmosphere of the ultra-hot Jupiter WASP-76 bSérgio Sacani
 
Climate Change Impacts on Terrestrial and Aquatic Ecosystems.pptx
Climate Change Impacts on Terrestrial and Aquatic Ecosystems.pptxClimate Change Impacts on Terrestrial and Aquatic Ecosystems.pptx
Climate Change Impacts on Terrestrial and Aquatic Ecosystems.pptxDiariAli
 
Human genetics..........................pptx
Human genetics..........................pptxHuman genetics..........................pptx
Human genetics..........................pptxSilpa
 
Thyroid Physiology_Dr.E. Muralinath_ Associate Professor
Thyroid Physiology_Dr.E. Muralinath_ Associate ProfessorThyroid Physiology_Dr.E. Muralinath_ Associate Professor
Thyroid Physiology_Dr.E. Muralinath_ Associate Professormuralinath2
 
FAIRSpectra - Enabling the FAIRification of Analytical Science
FAIRSpectra - Enabling the FAIRification of Analytical ScienceFAIRSpectra - Enabling the FAIRification of Analytical Science
FAIRSpectra - Enabling the FAIRification of Analytical ScienceAlex Henderson
 
Grade 7 - Lesson 1 - Microscope and Its Functions
Grade 7 - Lesson 1 - Microscope and Its FunctionsGrade 7 - Lesson 1 - Microscope and Its Functions
Grade 7 - Lesson 1 - Microscope and Its FunctionsOrtegaSyrineMay
 
(May 9, 2024) Enhanced Ultrafast Vector Flow Imaging (VFI) Using Multi-Angle ...
(May 9, 2024) Enhanced Ultrafast Vector Flow Imaging (VFI) Using Multi-Angle ...(May 9, 2024) Enhanced Ultrafast Vector Flow Imaging (VFI) Using Multi-Angle ...
(May 9, 2024) Enhanced Ultrafast Vector Flow Imaging (VFI) Using Multi-Angle ...Scintica Instrumentation
 
development of diagnostic enzyme assay to detect leuser virus
development of diagnostic enzyme assay to detect leuser virusdevelopment of diagnostic enzyme assay to detect leuser virus
development of diagnostic enzyme assay to detect leuser virusNazaninKarimi6
 
Exploring Criminology and Criminal Behaviour.pdf
Exploring Criminology and Criminal Behaviour.pdfExploring Criminology and Criminal Behaviour.pdf
Exploring Criminology and Criminal Behaviour.pdfrohankumarsinghrore1
 
Human & Veterinary Respiratory Physilogy_DR.E.Muralinath_Associate Professor....
Human & Veterinary Respiratory Physilogy_DR.E.Muralinath_Associate Professor....Human & Veterinary Respiratory Physilogy_DR.E.Muralinath_Associate Professor....
Human & Veterinary Respiratory Physilogy_DR.E.Muralinath_Associate Professor....muralinath2
 
Bacterial Identification and Classifications
Bacterial Identification and ClassificationsBacterial Identification and Classifications
Bacterial Identification and ClassificationsAreesha Ahmad
 

Dernier (20)

The Mariana Trench remarkable geological features on Earth.pptx
The Mariana Trench remarkable geological features on Earth.pptxThe Mariana Trench remarkable geological features on Earth.pptx
The Mariana Trench remarkable geological features on Earth.pptx
 
Stages in the normal growth curve
Stages in the normal growth curveStages in the normal growth curve
Stages in the normal growth curve
 
PATNA CALL GIRLS 8617370543 LOW PRICE ESCORT SERVICE
PATNA CALL GIRLS 8617370543 LOW PRICE ESCORT SERVICEPATNA CALL GIRLS 8617370543 LOW PRICE ESCORT SERVICE
PATNA CALL GIRLS 8617370543 LOW PRICE ESCORT SERVICE
 
module for grade 9 for distance learning
module for grade 9 for distance learningmodule for grade 9 for distance learning
module for grade 9 for distance learning
 
+971581248768>> SAFE AND ORIGINAL ABORTION PILLS FOR SALE IN DUBAI AND ABUDHA...
+971581248768>> SAFE AND ORIGINAL ABORTION PILLS FOR SALE IN DUBAI AND ABUDHA...+971581248768>> SAFE AND ORIGINAL ABORTION PILLS FOR SALE IN DUBAI AND ABUDHA...
+971581248768>> SAFE AND ORIGINAL ABORTION PILLS FOR SALE IN DUBAI AND ABUDHA...
 
Introduction of DNA analysis in Forensic's .pptx
Introduction of DNA analysis in Forensic's .pptxIntroduction of DNA analysis in Forensic's .pptx
Introduction of DNA analysis in Forensic's .pptx
 
Zoology 5th semester notes( Sumit_yadav).pdf
Zoology 5th semester notes( Sumit_yadav).pdfZoology 5th semester notes( Sumit_yadav).pdf
Zoology 5th semester notes( Sumit_yadav).pdf
 
Pulmonary drug delivery system M.pharm -2nd sem P'ceutics
Pulmonary drug delivery system M.pharm -2nd sem P'ceuticsPulmonary drug delivery system M.pharm -2nd sem P'ceutics
Pulmonary drug delivery system M.pharm -2nd sem P'ceutics
 
Velocity and Acceleration PowerPoint.ppt
Velocity and Acceleration PowerPoint.pptVelocity and Acceleration PowerPoint.ppt
Velocity and Acceleration PowerPoint.ppt
 
Asymmetry in the atmosphere of the ultra-hot Jupiter WASP-76 b
Asymmetry in the atmosphere of the ultra-hot Jupiter WASP-76 bAsymmetry in the atmosphere of the ultra-hot Jupiter WASP-76 b
Asymmetry in the atmosphere of the ultra-hot Jupiter WASP-76 b
 
Climate Change Impacts on Terrestrial and Aquatic Ecosystems.pptx
Climate Change Impacts on Terrestrial and Aquatic Ecosystems.pptxClimate Change Impacts on Terrestrial and Aquatic Ecosystems.pptx
Climate Change Impacts on Terrestrial and Aquatic Ecosystems.pptx
 
Human genetics..........................pptx
Human genetics..........................pptxHuman genetics..........................pptx
Human genetics..........................pptx
 
Thyroid Physiology_Dr.E. Muralinath_ Associate Professor
Thyroid Physiology_Dr.E. Muralinath_ Associate ProfessorThyroid Physiology_Dr.E. Muralinath_ Associate Professor
Thyroid Physiology_Dr.E. Muralinath_ Associate Professor
 
FAIRSpectra - Enabling the FAIRification of Analytical Science
FAIRSpectra - Enabling the FAIRification of Analytical ScienceFAIRSpectra - Enabling the FAIRification of Analytical Science
FAIRSpectra - Enabling the FAIRification of Analytical Science
 
Grade 7 - Lesson 1 - Microscope and Its Functions
Grade 7 - Lesson 1 - Microscope and Its FunctionsGrade 7 - Lesson 1 - Microscope and Its Functions
Grade 7 - Lesson 1 - Microscope and Its Functions
 
(May 9, 2024) Enhanced Ultrafast Vector Flow Imaging (VFI) Using Multi-Angle ...
(May 9, 2024) Enhanced Ultrafast Vector Flow Imaging (VFI) Using Multi-Angle ...(May 9, 2024) Enhanced Ultrafast Vector Flow Imaging (VFI) Using Multi-Angle ...
(May 9, 2024) Enhanced Ultrafast Vector Flow Imaging (VFI) Using Multi-Angle ...
 
development of diagnostic enzyme assay to detect leuser virus
development of diagnostic enzyme assay to detect leuser virusdevelopment of diagnostic enzyme assay to detect leuser virus
development of diagnostic enzyme assay to detect leuser virus
 
Exploring Criminology and Criminal Behaviour.pdf
Exploring Criminology and Criminal Behaviour.pdfExploring Criminology and Criminal Behaviour.pdf
Exploring Criminology and Criminal Behaviour.pdf
 
Human & Veterinary Respiratory Physilogy_DR.E.Muralinath_Associate Professor....
Human & Veterinary Respiratory Physilogy_DR.E.Muralinath_Associate Professor....Human & Veterinary Respiratory Physilogy_DR.E.Muralinath_Associate Professor....
Human & Veterinary Respiratory Physilogy_DR.E.Muralinath_Associate Professor....
 
Bacterial Identification and Classifications
Bacterial Identification and ClassificationsBacterial Identification and Classifications
Bacterial Identification and Classifications
 

A brief history on magnets

  • 1. A Brief History The history of magnets is shrouded in mystery and legend. Ancient History The most popular account for the discovery of magnets is a legend of a shepherd named Magnes who lived in Magnesia near Mount Ida in Greece Mount Ida was referred to as the "Mountain of the Goddess". Approximately 2,600 years ago (600 BC) while herding sheep on the mountain, Magnes found that the nails and buckle of his sandals and the tip of his staff were attracted to the rock he was standing on. He dug up the Earth to find lodestones. Lodestones contain magnetite, a natural magnetic material Fe3O4. The word magnet is derived from the Greek name magnetis lithos, the stone of Magnesia, referring to the region on the Aegean coast in present-day Turkey where these magnetic stones were found. Middle Ages History The Chinese provide the first documented use of suspended lodestones used as a compass. In 1088 Shen Kuo described the magnetic needle compass, which could be used for navigation in his Dream Pool Essays. The first recorded use was documented by Zheng He of the Yunnan province. Between the years 1405 and 1433, Zheng He recorded his voyages across seven oceans. In approximately 1180, Englishman Alexander Neckam records the earliest European understanding of the magnet as a guide to seamen, the early compass. The term lodestone comes from the
  • 2. Anglo-Saxon meaning "leading stone," or literally, "the stone that leads." The Icelandic word is leider-stein, and was used in writings of that period in reference to the navigation of ships. Modern History In 1600, English scientist William Gilbert confirmed earlier observations regarding magnetic poles and concluded that the Earth was a magnet. In 1820, the Dutch scientist Hans Christian Oersted discovered the relationship between electricity and magnetism, and French physicist Andre Ampere further expanded upon this discovery in 1821. In the early 1900s, scientists began studying magnetic materials other than those based on iron and steel. By the 1930s, researchers had produced the first powerful Alnico alloy permanent magnets. In 1966 the first rare earth magnets were developed from Samarium-Cobalt (SmCo5) producing a high energy product of 18 MGOe. In 1972 further developments were made using Samarium-Cobalt (Sm2Co17) to produce a higher energy magnet product of 30 MGOe. In 1983 General Motors, Sumitomo Special Metals and the Chinese Academy of Sciences developed a high energy product of 35 MGOe from a compound of Neodymium-Iron-Boron (Nd2Fe14B) referred to as neo magnets or rare earth magnets. The enormous interest these magnets have generated arises because, for the first time, a new magnetic material has been introduced which is not only stronger than the previous generation but is more efficient. Neo magnets are the strongest type of permanent magnet in the world.
  • 3. Today magnets play a role almost every technologically advanced device we use, including computers, automobiles, industrial sorter and seperators, power generators, speakers, cell phones etc.