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How does one define an electric field?

  1. Jul 16, 2009 #1
    How does one define an electric field??

    How does one define an electric field??
  2. jcsd
  3. Jul 16, 2009 #2


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    Re: Electricity

    Via the Maxwell Equations.

    {ambiguous questions get ambiguous answers}

  4. Jul 16, 2009 #3
    Re: Electricity

    What are the maxwell equations??
  5. Jul 20, 2009 #4
    Re: Electricity

    I think the simplest way to define an electric field is mathematically. That equation is E=kQ/r^2

    E is electric field in Newtons per coulomb
    k is the coulombs constant which is 9E9 (the units are Nm^2/C^2)
    Q is the present charge in C
    r is the distance away from the charge in meters

    That's the simplest way to define an electric field I think.

    The other way to define an electric field is by using this equation


    F is the force between 2 electric particles in newtons
    q is the charge measured in coulombs

    hope this helps
  6. Jul 21, 2009 #5
    Re: Electricity

    The force per unit charge that a positive charge would experience if it were to be inserted into a region of space, where the force is caused by the existence of one or more other charges.

    Hover said: E=kQ/r^2
    But it wasn't part of the question to assume that the field is caused by one point charge. For example, between two charged parallel plates the electric field is close to being a set of parallel lines with constant magnitude.
    Last edited: Jul 21, 2009
  7. Jul 22, 2009 #6
    Re: Electricity

    Checkout the attached PDF...those are the parts of my notes.

    Attached Files:

  8. Jul 22, 2009 #7
    Re: Electricity

    An electric field is an area of space where something experiences a force due to its charge
  9. Jul 22, 2009 #8


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    Re: Electricity

    True, but the same can be said about a magnetic field too in the case of moving charges.
  10. Jul 22, 2009 #9
    Re: Electricity

    This may be true, but that is the formal definiton of an electric field
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