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Homework Help: Electric field question

  1. Feb 16, 2012 #1
    The question is in the paint doc....

    What I did...

    1st eq.
    v = kq/r

    q = vr/k

    2nd equ.

    E = kq/r^2

    where am I going wrong...? For E I am getting 2500

    Attached Files:

    • ph.jpg
      File size:
      17.4 KB
  2. jcsd
  3. Feb 17, 2012 #2


    User Avatar
    Homework Helper

    The potential is not linear function of the distance, it changes 25 V from the second circle to the third one, and 50 V from the third circle to the fourth. The electric field is negative potential gradient, -ΔV/Δd. Use both circles, below and above the point shown to get it.

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