– From the ten most beautiful experiments by George Johnson
Michael Faraday, a great English scientist, was known for his experiments and was also a devoted Christian. Ada Lovelace, despite being considered troublesome, played a key role in inspiring Faraday. In 1844, Ada engaged in a flirtatious exchange with Faraday, suggesting she be his muse. This encouragement likely motivated Faraday to demonstrate that electrode magnetism is closely linked to light, adding to his significant contributions in electricity and magnetism.
Michael Faraday worked for the Royal Institution in London, where he did important scientific work. In the late 1820s, Humphry Davy, an English chemist, told Faraday about Hans Christian Oersted creating a voltaic battery using acid-filled vessels, copper, and zinc. Oersted observed that when he connected a wire from the battery to a compass, the needle moved west or east based on the wire’s placement. Andre-Marie Ampere also found that parallel wires with currents in the same direction attracted like magnets, and reversing one current made them repel. This discovery highlighted the clear connection between magnetism and electricity.
In the past, Newtonian mechanics didn’t predict forces moving in circles, but Faraday demonstrated otherwise. Using basic materials like mercury and cork, he made an electrified wire spin around a magnet and vice versa, creating an electric motor. By shaping a wire into a loop connected to a battery, he made a weak magnet, and if the wire was spiraled, the magnetic force became stronger, focused on the coil’s center. The following decade focused on steel and copper metallurgy, glass manufacturing, and other tasks of the industrial age.
During a summer day, Michael Faraday observed the effect of placing two coils close to each other. He wound 72 feet of copper wire around one side of an iron frame, calling it coil A. On the opposite side, he wound coil B with about 60 feet of wire. Despite no direct connection between the coils, touching coil A’s wires to a battery caused a galvanometer connected to coil B to move. Faraday imagined an electric wave traveling through the ring, inducing a current in the second coil—this was electromagnetic induction, revealing a new world. Faraday, who had earlier converted magnetism to electricity, now created the first basic electrical dynamo. He realized that electricity could produce motion and vice versa. Over time, he observed changes in voltaic cells, suggesting a transformation of energy types. When electrified wires were in a salty solution, hydrogen collected at one end and oxygen at the other, showcasing the link between electricity and chemical reactions.
In late August 1845, Michael Faraday set up an important experiment in his lab. He aimed to see if an electrical current could twist the direction of a light beam. He filled a trough with a slightly conductive solution, placed platinum electrodes at each end connected to a battery, and passed light through the solution. Despite trying various setups, including using strong batteries and static electricity, he saw no change in the light. Then, he tried using magnetism. Michael Faraday placed a thick optical glass near a powerful electromagnet, allowing horizontal light waves to pass through it. When he turned on the magnet, the light beam rotated, showing that a magnetic field could influence the direction of light.
Faraday discovered that a strong permanent magnet could also turn the light beam, and he found that transparent materials other than glass could be used. He went further, trying to link gravity and magnetism but noted in his diary, “ALL THIS IS A DREAM.”
The discoveries from Hans Christian Oersted and Andre-Marie Ampere were crucial in Michael Faraday’s discovery of electromagnetic rotation. Which is the principle behind the electric motor. Faraday then built the first electric generator and transformer which today is a cornerstone in powering devices from household appliances to industrial machinery. Faraday’s impact extends to medical imaging with MRI machines which use powerful magnets to generate strong and stable magnetic fields. When the body nuclei are exposed to radiofrequency pulses the magnetic fields emit signals which are detected by the MRI machine for the detailed and high resolution of internal body structures. Faraday’s discoveries have driven innovation in our current world that enhance our daily lives and drive progress across many industries.
Faraday’s eagerness to explore was captured in his quote: “Nothing is too wonderful to be true if it follows the laws of nature, and experiments like these are the best way to test such consistency.”