Monthly Archives: January 2015

Our Cambridge colleagues about Tesla

Deepyanti Taneja, Tesla Memory project’s friend and colleague is a  PhD student in Semiconductor Physics @ Cavendish Lab; St Catharine’s College, University of Cambridge

Cavendish Cambridge

Nikola Tesla: The man who made the world alternate

He who burnt the midnight oil; he who toiled day in and day out; a man, named Nikola Tesla, ought not to be forgotten. This small article is a modest attempt to pay tribute to one of the greatest inventors of all times who contributed profoundly to the scientific advancement in the fields of electricity and magnetism so the world could function how it does today.

Tesla was bestowed with an investigative turn of mind. Even as a very young child, he would question nature’s workings and go to unimaginable extremes to find his answers. Legend has it that, one time he attempted to fly from the roof of a barn using an umbrella with the intention of unravelling the mysteries of aeronautics. The exercise left his body battered and the family umbrella broken but did not deter his spirits to keep questioning and discovering! Scientific inquisitiveness and the ability to unearth nature’s answers came naturally to Tesla but sadly this talent of his was not appreciated fully by his family. When complimented upon the inventive ability of his son, Tesla’s father would immediately make the complimenting friends aware that Nikola was to become a priest as he was promised to the ministry. Young Tesla did not want to go against his parents’ whims and desires for him but he never felt that he could do justice to any career, which did not deal with science and discovery. The great, self-imposed, disciplined character that people often associate with Tesla was the outcome of several years of rugged military life that he had experienced as a young boy. The immense possibilities that imposing self-control and willpower held in them appealed hugely to him and he began depriving himself of things that he craved for the most. He has been quoted as saying, “At first it called for a vigorous mental effort directed against my disposition and desire, but as years went by the conflict lessened and finally my will and wish became identical.” It is these kinds of self-depriving, always giving and never wanting anything in return characters who leave behind so much for their future generations that we shall remain indebted to them forever!

As a scientist, Tesla’s greatest contribution to today’s society was made during the time of the ‘War of Currents’. Thomas Edison, widely known as the inventor of the electric bulb was at conflict with Tesla, who had found many caveats in Edison’s way of current generation and distribution. Edison’s bulbs were supplied by direct current (DC), where the charge carriers carrying current always flow in one direction. One serious disadvantage of using DC was its inability to travel large distances (typically more than 2 miles) since it couldn’t be stepped up to high voltage levels required for long distance transmission. As a consequence, there was a need to establish direct current power stations at an interval of every 2 miles; not a very economically favourable solution for electricity distribution. Tesla, on the other hand, thought of all energies as being cyclic and was in favour of alternating current (AC), where the charge carriers change direction 50 or 60 times per second. Alternating current can be stepped up or down using step-up or step-down transformers and can be transmitted over huge distances thereby circumventing the need to have closely spaced power stations. Despite the anti-AC campaign led by Edison, the advantages of using AC for electricity transmission were many. AC prevailed and is the system we currently use to supply electricity throughout the world.

A brilliant scientist on one hand, Tesla often also came across as a veritable magician and an excellent showman with his outstanding demonstrations. One of his demonstrations, which caused a sensation amongst the audience, was the presentation of bulbs, which would light up without the use of any wires but simply by movement within the electrostatic field set up between two zinc sheets connected to his oscillating transformer. This performance left the audience enthralled and hungry for more breathtaking spectacles that Tesla promised to present in the future. During the same lecture, concerned about the safety of the audience, Tesla also presented a physiological experiment where he connected his body across a potential difference of some 2,50,000 Volts and let the full current pass through him. He was left unharmed due to the current remaining on the surface of his body, which he explained as the skin effect.

I am reminded of Nikola Tesla every time I scribble the magnetic field (in units of Tesla!) I apply to my nanodevices in my lab notebook. In addition to the umpteen technological inventions that Tesla gave rise to; the ways in which he has contributed to the field of fundamental Physics is unrivalled. He shall always remain a Physics hero for all the budding scientists like me.