Michael Faraday


In the scientific field of electromagnetism, its foundation can be accredited greatly to the contributions of one man. Regarded by many as one of the greatest experimenters that ever lived, Michael Faraday formulated much of the theoretical and experimental data that would lead to the classical electromagnetic field theory, also undertaking much experimenting in the area of chemistry. He is remembered for his groundbreaking and innovative experimentation, as the first scientist to record the production of an electric current by use of a magnetic field, as the inventor the electric motor, and as the inspiration for the naming of the SI unit of capacitance, the farad. He also demonstrated the relationship between electricity and chemical bonding, the effects of magnetism on light, and he discovered diamagnetism, which is the behavior exhibited by certain substances in a magnetic field. A scientist renowned for his pioneering experimentation into electromagnetism, Michael Faraday’s work has eternally inspired the scientific world.¹

Insight and Influence


Born on September 22, 1791, Faraday first became interested in science while he read books, during the time he was apprenticed to a bookbinder.² However, he did not begin his scientific career until 1811, when he attended the lectures of the chemist, Sir Humphrey Davy, who would become the greatest influence on Faraday‘s life. After sending the lecture notes that he recorded to Davy, at the age of 21, he was appointed a lab assistant by Davy in the Royal Institution in London. Faraday’s first experiments were in the area of chemistry, his experimentation with electricity and electromagnetism not beginning until 1821. The insight behind Faraday’s experimentation with electricity was his belief that electricity is one of the manifestations of the unified force of nature. The field of electromagnetism was still new at this time, with major experimentation only being carried out by Charles Coulomb in 1785 and Christian Oersted and Andre Marie Ampere in 1820. Their experimentation discovered that electric currents could produce magnetic fields , on which Faraday expanded, believing that a magnetic field could also produce an electric current, an achievement he accomplished in 1831. In 1845 Faraday discovered a new effect, now known as the Faraday effect, which was the ability of a powerful
Faraday.jpg
Michael Faraday and an early electrical battery. Painting by Thomas Phillips, 1842, National Portrait Gallery. Image from BRITS AT THEIR BEST.com ¹⁴
magnetic field to rotate a plane of polarized light. As Faraday’s mental health began to fail, in 1855, his experimentation was greatly reduced, however, he still continued to present lectures.³ Throughout Faraday's life he was devoted to the Christian sect of the Sandemanian Chuch, and he maintained the belief that God and nature were unified.¹

Major Contributions


All of Michael Faraday’s major contributions and discoveries to science were in the area of electricity and electromagnetism, including Faraday’s Law of Induction, Faraday’s Laws of Electrolysis, the Faraday Cage, and the Faraday Effect. In 1831, Faraday began is experimentation on what he would discover to be induction. Making a breakthrough experiment on August 29, 1831, Faraday, using one of his induction rings, generated an electric current in a wire by using the electromagnetic effect of another wire, making the first electric transformer, and in a series of experiments the next month he was able to produce a steady electric current, making the first generator, by attaching two wires through a sliding contact to a copper disc, rotating the disc between the poles of a horseshoe magnet, and obtaining a continuous direct current. Through these experiments, Faraday developed what is now known as Faraday’s Law of Induction, which states, “the induced electromotive force in any closed circuit is equal to the time rate of change of the magnetic flux through the circuit.” Simply put, an electric field is produced on any conductor of electricity, anywhere where there is a change in a magnetic field over time, and the rate of change of the electric current is directly proportional to the change of the magnetic field. The experimentation conducted by Faraday on the electrolysis, which is a method of dividing chemically bonded compounds using an electric current, was inspired by an earlier experiment by his predecessor Humphrey Davy. Davy’s experiment discovered that the metals sodium and potassium can be precipitated from their compounds through electrolysis, and in 1832, Faraday created two laws on electrolysis. Faraday’s first law states that, "the amount of any substance deposited, evolved, or dissolved at an electrode is directly proportional to the amount of electrical charge passing through the circuit." This basically means that larger electric charges will alter more of the target substance at an electrode. This led to Faraday’s calculation of the magnitude of electric charge that is in one mole of electrons, which is 96.4853 kilocoulombs, now known as Faraday’s Constant(F). Faraday’s second law states that, "The mass of different substances produced by the same quantity of electricity are directly proportional to the molar masses of the substances concerned, and inversely proportional to the number of electrons in the relevant half-reaction." This basically means that y moles of electrons are needed to discharge an ion Xy+ or Xy-. Faraday's next major accomplishment in applied science was the Faraday Cage, the first he created, being a room, which was coated in foil that he passed a high voltage electric current through. Faraday had discovered that no large electric fields were present in the cage because, the surface tended to redistribute the charge so that any field inside the cage was canceled out. Faraday cages are useful in containing electric fields as well as preventing them from entering the interior of the cage, and can be used to protect electrical equipment from harmful fields. The Faraday Effect was discovered in 1845 in another experiment, which was an interpretation of the rotation of a plane of light through a magnetic field. In the experiment, he shined a polarized ray of light through a high refractive index of glass, and turned on an electromagnet with the lines of force parallel to the plane of light. The electromagnet caused the light plane to rotate, and, therefore, provided more evidence to Faraday's lines of force.

Affect and Effect


Michael Faraday was born on September 22, 1791 to a blacksmith and a country woman in Newington, Surrey, which is near London, England. He lived a difficult childhood in a poor family, obtaining only a primary education. At 14 years old, he began his apprenticeship to a bookbinder, which lasted for six years. During these years he read many books and became interested in science, even constructing his own electrostatic generator from bottles and unused lumber. After becoming an apprentice to Sir Humphrey Davy in 1812, Faraday learned much about chemistry. His apprenticeship ended in 1820, which is also the same year that he produced the first two compounds of carbon and chlorine, his first major accomplishment as a scientist. The next year, Faraday married his wife, Sarah Barnard, and he began his first experimentation into electrochemistry, and after Davy’s health failed in 1825, Faraday assumed his position as director of the laboratory in the Royal Institution. Also in 1825, Faraday achieved his second major accomplishment in chemistry, when he was able to isolate the gas, Benzene. Faraday’s first major accomplishment in electromagnetism came in 1831, when he created his law of induction, which was followed a years later by the creation of his two laws of electrolysis, and in 1833 with his appointment to the Fullerian Professorship of Chemistry, a research chair created especially for him. In 1839, Michael Faraday proposed a new theory on electrical action, which stated that objects that built-up and broke-down electrical charges in a cyclic manner due to electrical strain were conductors, and objects that were able to take enormous strain from electricity were insulators, and the amount of strain from electricity that an object could take was related to its chemical make-up. However, his health broke down that year from the previous stressful eight years of experimentation, and he made no more advancements until 1845. That year he discovered the Faraday Effect, and he discovered that everything produced some form of magnetic field in response to an applied magnetic field, a term which he coined as “diamagnetism.” Throughout his career as a scientist, Michael Faraday searched for evidence for lines of force, which are chains of polarized particles in a dielectric, and his theories were criticized by other scholars who had differing beliefs. However, in 1850, Faraday used his lines of force to propose his electromagnetic field theory, which stated that energy in the universe was not confined to the particles that created the force, but instead were found surrounding the particles in space, which he believed was a medium capable of conducting electric and magnetic forces. His belief in lines of force was strengthened in 1852, when he published a piece of literature: “On the physical character of the lines of magnetic force,” in which he describes lines of force as “those lines which are indicated in a general manner by the disposition of iron filings or small magnetic needles, around or between magnets.” After the failure of his mental health in 1855, Faraday’s experimentation for the most part ended, except for certain experiments on the conversion of gravity to magnetism, which were never published due to negative results, and he only gave lectures, many of which were presented to children, a series of six being published in 1860, as “The Chemical History of a Candle.” In 1861, Michael Faraday ended his lecturing, and soon after, Faraday accepted a house at Hampton Court, where he died on August 25, 1867, from Queen Victoria and was offered the honor of knighthood and the position as President of the Royal Society, both which he declined, saying, “I must remain plain Michael Faraday to the last; and let me now tell you, that if I accepted the honour which the Royal Society desires to confer upon me, I would not answer for the integrity of my intellect for a single year.”¹⁰

The Things he Left Behind


Michael Faraday has made many contributions to the world of science and has left a lasting legacy in the fields of electricity, electromagnetism, and electrochemistry. Faraday's first lasting discovery was of the toxic liquid, Benzene, which has become a major industrial solvent, now used in plastic, synthetic rubber, nylon, some pharmaceutical drugs, and some explosives.¹¹ Faraday was able to make use of electricity as technology, in 1831, and Faraday’s ideas and theories from testing electromagnetism led to the formation of the classical electromagnetic field theory by the Scottish physicist, James Clerk Maxwell. The electromagnetic field theory for which Faraday laid the foundations is extremely significant because on it grew practically every part of the electrical industry, including telephones, the use of motors for power, and everything that uses dynamo, or generator to induce an electric current.¹² The Faraday cage is another concept developed by Faraday that is now part of what people use everyday. The concept is used in microwaves, generators, anything that provides a shield from electromagnetic forces, and many radio frequency generating devices are protected by a Faraday cage to prevent electromagnetic interference.¹³ Thanks to Faraday, today, people are able to live more comfortably with electric appliances and other items, which could not exist in the same magnitude as they do without his groundbreaking work and achievements in electricity and electromagnetism.






References


1. Micheal Faraday: http://people.clarkson.edu/~ekatz/scientists/faraday.htm
2. BBC-History-Michael Faraday (1791-1867): http://www.bbc.co.uk/history/historic_figures/faraday_michael.shtml
3. Michael Faraday: http://www.phy.hr/~dpaar/fizicari/xfaraday.html
4. Faraday's Law of Induction: http://www.answers.com/topic/faraday-s-law-of-induction
5. Faraday's Laws of Electrolysis: http://www.physchem.co.za/OB12-che/electrolysis.htm
6. Faraday Cage: http://www.electro.patent-invent.com/electricity/inventions/faraday_cage.html
7. Faraday's Law of Induction: http://www.answers.com/topic/faraday-s-law-of-induction
8. The Faraday Effect: http://www.mmresearch.com/articles/article3/
9 Milestones of Science-Michael Faraday: http://milestones.buffalolib.org/books/books/character/character.htm
10. Dictionary of Science Quotations and Scientist Quotes-Michael Faraday: http://www.todayinsci.com/F/Faraday_Michael/FaradayMichael-Quotations.htm
11. Wise Geek-What is Benzene?: http://www.wisegeek.com/what-is-benzene.htm
12. Wise Geek-Who discovered Electricity?: http://www.wisegeek.com/who-discovered-electricity.htm
13. Wise Geek-What is a Faraday Cage?: http://www.wisegeek.com/what-is-a-faraday-cage.htm
14. BRITS AT THEIR BEST.com: http://www.britsattheirbest.com/ingenious/ii_19th_century_1800_1831.htm