Michael Faraday
and
His Discoveries
Faraday the book binder and an autodidact
As every science student knows, Michael Faraday was one of the greatest scientists of 19th century. What is incredible and inspiring is this great scientist, who lacked formal education and worked as a bookbinder for living from the age of 13, could teach himself all that were needed to do science and ultimately could make discoveries that would change the world for ever.
But what exactly did he discover? What made him so great? Keep reading.
Faraday's Discoveries
Firstly, he was the first scientist to demonstrate the principle of electric motor and dynamo. Secondly, he introduced new concepts like magnetic induction and magnetic field in physics. Thirdly, he made great discoveries in electro chemistry too.
In addition, he collaborated with James Maxwell and unified three fields of physics – electricity, magnetism, and light – and predicted the existence of electromagnetic waves.
Bookbinder to Scientist
With no formal education, what transformed Faraday’s life were the Royal Institution and Sir Humphry Davy.
Davy, a well-known scientist and the director of the Royal Institution, invented the safety lamp for the coal miners, and he also discovered elements like sodium and potassium. After attending one of the Davy’s spell-bound lectures at the Royal Institution, Faraday decided to work for Davy and requested a job at Royal Institution. Davy offered him the only position that was available: a bottle cleaner.
Yes, Faraday’s Science life started at the Royal Institution as a bottle cleaner.
Impressed with his knowledge and meticulous documentation, Davy soon recognized Faraday’s talent, and they started working together. He not only mentored Faraday but also let him perform experiments and publish papers on his own.
Eventually, Faraday became the director of the Royal Institution.
Let us first take a look at how he discovered the principle of electric motor.
Oersted's Discovery
In 1820, Hans Christian Oersted, professor of physics at the university of Copenhagen, discovered that when a magnetic compass was placed near a current-carrying wire, it turned quickly and stayed right angle to the wire. Oersted discovered that a current-carrying wire produced magnetic effect.
This discovery jolted the scientific community.
Oersted's discovery made Faraday and other scientists realize that electricity and magnetism were linked somehow. But they were not sure how. Though other scientists like Ampere and Coulomb theorized Oersted's discovery using mathematics, Faraday felt that the current-carrying wire induced a circular magnetic force in space around itself and that magnetic force caused the needle to turn.
The First Electric Motor
While experimenting on this, Faraday successfully demonstrated the principle of electric motor. He built a simple apparatus using a container, a magnet, mercury, and a battery. When he turned the switch on, ah, the hanging wire started moving in rapid circles around the magnet.
The first electric motor was born in 1821. However, it took 10 more years to demonstrate the principle of dynamo.
Magnetic Induction
And Dynamo
By 1831, everyone knew how to make magnetism from electricity. The obvious question was, should it not be possible to produce electricity from magnetism? But the answer eluded everyone. Finally, Faraday's one of the experiments with a huge iron ring with a battery connected to a primary circuit just produced a twitch in the secondary circuit when the primary circuit was switched on or off. But there was no continuous current.
Faraday then tried with a coil and a permanent magnet. As shown in the picture on the left, when the bar magnet was plunged into the coil, he noticed current in one direction, and when the magnet was pulled out, current was flowing in the opposite direction.
And that was the moment of the discovery of magnetic induction and the birth of dynamo.
Modern Power Generation
Modern dynamos and generators, however advanced it could be, operate on the same magnetic induction principle that Faraday discovered in 1831. As depicted in the simple picture on the right, a coil is surrounded by a permanent magnet, and when the coil is rotated by means of thermal or hydro or nuclear or wind power, the relative motion causes magnetic induction in the coil and results in continuous electricity.
Impact of his discoveries
When Faraday demonstrated the principle of electric motor in 1821 and the principle of dynamo in 1831, people then did not realize how those discoveries were going to change the world. Even Faraday himself was not sure of their applications.
Today, we are well aware of their applications and how indispensable these applications are. All the modern-day conveniences that make our lives better and the world relies on heavily, such as electricity, wireless communication, satellite, radar, radio, TV and computer etc., depend on this man’s amazing discoveries and ideas.
Collaboration with Maxwell
Faraday collaborated with James Maxwell, who was a Cambridge educated mathematical physicist, to unravel some of the mysteries of physics, and they unified three different fields of physics – electricity, magnetism and light. Faraday’s idea of electromagnetic field and magnetic induction were later packaged by Maxwell in the form of sophisticated mathematical equations.
Their groundbreaking work led to many other discoveries including the special theory of relativity by Albert Einstein.
Faraday's contributions
Following is a summary of Faraday's major contributions to Science. Certainly, this is NOT a complete list.
Laws of magnetic induction
Field theory
Principle of electric motor
Principle of dynamo
Principle of Transformer
Polarization of light in magnetic field
Laws of electrolysis
Faraday’s cage
Words coined by Faraday:
Lines of force
Magnetic induction
Magnetic Field
Electrolysis
Electrolyte
Anode
Cathode
Ion
Anion
Cation
Ferro magnetic
Para magnetic
Diamagnetic
Isn’t it amazing that a self-taught scientist, with no mathematical education, could contribute so much to science? No doubt, it was his curiosity combined with relentless pursuit to discover the laws of nature that made everything possible.
No surprise, Faraday was one of the heroes of Albert Einstein.
In Faraday’s honor, the unit of capacitance is named after him. It is farad.