Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Electrical arc's e-field

  1. Apr 4, 2010 #1
    ok, so I've got an arc between two electrodes. What is the direction of the electrical field if there is an electrical field?
     
  2. jcsd
  3. Apr 4, 2010 #2
    it's probably more appropriate to put this in the homework sections. ( since this problem seems purely theoretical and i don't see how you could be dealing with this in real life)

    i don't really know, but my guess it away from the arc, since it may be a bunch of electrons moving through air. however, it's probably not so simple since the air turns into plasma.
     
  4. Apr 4, 2010 #3

    vk6kro

    User Avatar
    Science Advisor

    Electrons in an arc follow the direction of an electric field.

    The electric field is between the two electrodes.
     
  5. Apr 4, 2010 #4
    just out of curiosity, would the arc itself generate a field?
     
  6. Apr 4, 2010 #5

    vk6kro

    User Avatar
    Science Advisor

    Yes, but a magnetic field in the form of a circular pattern concentric with the arc. This is no different to a current flowing in a wire.

    337px-Manoderecha.svg.png
     
  7. Apr 4, 2010 #6
    that was my guess, dvchench, but for what i'm doing i hope vk6kro is right.
     
  8. Apr 4, 2010 #7
    thanks dvchench, that pretty much confirms what i thought.
     
  9. Apr 4, 2010 #8
    ...and vk6kro
     
  10. Apr 4, 2010 #9
    doesn't a wire with current flowing through it have a surface charge density along its circumference that generates an e-field away from the center of the wire? can't quite remember that part of EM1 that well... I know that was the basis of most of our image theory problems -- a high-voltage, high-current "power line" above the earth-ground plane generating an E-field.
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook