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Length and Area Elements

  1. Oct 6, 2008 #1
    I'm having a difficult time figuring out how to find length and area elements for Gauss's, Ampere's, and Biot-Savart Laws! Can someone please help explain! This applies to symmetrical, non-symmetrical, and infinite objects! I'm not asking what is the area of a sphere but, say with an infinite object, you use a small portion maybe called ds, well how do you figure how what your value of ds will be? And please don't give an example using a simple figure! That won't help me! I've noticed that if I understand the most difficult then I'm good to go for everything!! Thanks :)
  2. jcsd
  3. Oct 6, 2008 #2
    ds is an infinitesimal distance which u can chose in cartesian coordinates, cylindrical or spherical coordinates. U want to chose ds along the line which contains the flux or the current, ...
  4. Oct 6, 2008 #3


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    You don't "figure out your value of ds". A differential has no value in terms of numbers. You integrate with respect to s.
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