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Did i calculate the V/A/R of a plasma arc properly?

  1. Feb 24, 2017 #1
    Hello there! So i am currently sitting in my EME class and have nothing to do, so i decided to try spit-balling the V/A/R of the plasma arc my Tesla Lighter produces. note that i did not physically take it apart, and my goal was just to get a rough estimate for the arc itself or at least get a minimum rating, not the circuit inside. Please tell me if i did something wrong or improperly assumed something, im only afew months into this class and am still learning but heres how my logic follows:
    Voltage- To get the minimum voltage i had to determine the length between the positive and negative ends that the arc stretches across which is 5 centimeters. I then did some research and found that it takes 3×10^6 V/m of air for an arc to jump across. I then divided that by 100 and multiplied by 5 to get 150,000 volts to stretch an arc 5 cm.

    Resistance- To get the overall resistance i did some more research and found that air has a resistance of 4x10^13 ohms per meter (it varies a lot but this is probably a good range) and simply divided by 100 and multiplied by 5 again to get 2x10^12 ohms.

    Amperage- Finally to find the amperage i used ohms law for I=E/R. I= 150,000 / (2x10^12) to get I=7.5x10^-8 amps.
    So that sums up the process i used, please let me know if i did anything incorrect and if my reasoning was flawed. Just to re-iterate this is just a thought experiment and i am not going to use this line of educated assumption for anything besides food for thought. Thanks again!
  2. jcsd
  3. Feb 24, 2017 #2


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