Who doesn't love fireworks? Fireworks are the center of Christmas and new year celebrations, everyone is happy when fireworks are used to grace the event. This reminds me of my childhood days, when we would be so eager to receive them from our parents. If for any reason they forgot to buy fireworks for Christmas, we would disturb them and sometimes even shed some crocodile tears to convince them to rethink their decision of not buying fireworks. Those good old days.
Even till now I still find fireworks amusing and am sure others - even you reading this post also find it amusing. What if I were to tell you that you could save yourself some money and buy yourself a transformer - The Irony. Yes, transformers create good and more radiant fireworks, even better than the real deal.
They are so spectacular and shinning, that I figured I should share this information. "Seeing is believing you say?" - obviously you are doubting because you haven't seen a transformer in action. Alright, let me show you a real transformer in action ->
"I hope you are satisfied by seeing". The idea of having transformers as fireworks at first seemed unbelievable but for some reason now you believe and for some other reason you want to know what it is, how it is possible, why it is possible and so many other questions you cant even pen down. It is with joy that I will go over this questions as it is my desire to disseminate useful information.
The lighting that the transformer performs is called electric arcing. For formal sake "arcing is a phenomenon that occurs when air surrounding two separate conductors ionizes and becomes conductive, resulting in a continuous electric discharge."
So what we really see is, conductive air. "We were taught that air is a poor conductor" - that is indeed true, but what you were not taught was that at a particular voltage, air breaks down and ionizes, meaning that eventually, it becomes a conductor at a particular voltage just like every other non conductors or poor conductors like neon gas, silicon etc. This voltage at which air conducts is known as its * breakdown voltage.*
The breakdown voltage of the gas, in this case, air, is highly influenced by the atmospheric pressure, the distance between the electrodes and the type of the gas. According to Paschen's law the lower the pressure the lower the breakdown voltage required, the shorter the distance apart the lower the breakdown voltage required. But this law is only followed up to a point, as any further reduction in pressure or the air gap as the case may be will cause an increase in breakdown voltage.
The electric discharge produces heat and ionizes more surrounding gas (air) molecules, creating more mobile current-carrying ions, making more current flow. That is why electric arcing is characterized by high current density. Current density as high as 1,000,000 amperes per square centimeter can be recorded. That is to say, in an arc of let's say 1m x 1m, we would have as much as 100 amps of current flowing.
The human body alone allows a maximum current of less than 10mA to flow through it and anything beyond that is regarded as dangerous. Meaning that electric arcs are extremely dangerous to the human body and contact with it should be avoided - unless you want to really see the effect, that is, if you survive. Lolz.
As we can easily be deduced, the current flowing through the arc is sustained by the heat from the actual electric discharge and the field generated by the high voltage.
The interesting fact about electric arcs is that they can occur in both DC and AC. Buth with AC, the polarity of the electrodes interchange within each cycle.
It is good that I mention here that the regular lightning we see when rain is falling is not regarded as electric arcing but rather sparking. The difference between the two is that arcing is continuous even after the two electrodes that started it is disconnected, meanwhile sparking is discontinuous.
Despite, the fact that electric arcing is dangerous when in contact with the human body it still finds use or application in several fields and devices.
Electric arcs are used by welders to join metals of different kinds, by the process known as electric arc welding. The arc is initiated by touching the workpiece with the electrode and withdrawing it a little distance from the workpiece until a stable arc is formed. The heat generated from the arc is what actually joins the metals together through the fusion of the two metals.
Electric arcs are used in gas discharge lamps, that produce light by an arc between two electrodes through an inert gas in a glass bulb. Arc lamps were widely used during the 80s for lighting streets and large buildings but were later replaced by the incandescent lights.
Electric arcs are also used in electric arc furnaces to purify by heating, various metals like steel. The metal scraps are first charged by preheating them before they are transferred to the furnace, an arc is then stuck and the heat produce melts the metal scrap in the furnaces.
Watching the arcing of transformers afar off is really beautiful and amusing - "I even consider them, fireworks". Despite all the dangers ascribed to it, they are really helpful and used in some fields and devices.
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