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Homework Help: Equipotential lines -

  1. Jul 20, 2010 #1
    1. The problem statement, all variables and given/known data

    Sketch the equipotential surfaces which result from the following charge configurations:
    (a) a point charge
    (b) a spherically symmetric charge distribution
    (c) a very large, plane, uniformly-charged sheet
    (d) a long, uniformly-charged cylinder
    (e) an electric dipole.

    sorry I have posted this already but i figured since i mainly just need a check id stick it in a different thread.
    I am pretty sure that a and e are correct, unsure of b and d and I need some help with c... thanks

    2. Relevant equations

    3. The attempt at a solution

    Attached Files:

    • equi.jpg
      File size:
      18.7 KB
  2. jcsd
  3. Jul 20, 2010 #2
    It might help understanding to think about these in terms of http://hyperphysics.phy-astr.gsu.edu/Hbase/electric/gaulaw.html" [Broken].

    B is wrong. D is probably better drawn in 3D if you can. For C, think about the gravitational field right at the surface of the earth - this is a good approximation.
    Last edited by a moderator: May 4, 2017
  4. Jul 20, 2010 #3
    sorry but could you give me a bit more of a hand - ive never heard of Gauss' law (excluding the million things in maths he did) D i dont think i can draw in 3d???, b i have no idea what else to do and c i will look at the gravitational field right at the surface of the earth now
  5. Jul 20, 2010 #4
    What will B look like from a huge distance away? (Think about stars in the sky!!! :rofl:)

    D is misleading in 2D. If the marking is really picky it might even be wrong - remember how to draw field lines into and out of a page? to draw in 3D just draw a coke can, then rub out the ends or something!
  6. Jul 20, 2010 #5
    been a year since i did this in high school but i think that x means out of page and dots mean in??
  7. Jul 20, 2010 #6
    is this what you meant for d????? (really dodgy)

    Attached Files:

    • d.png
      File size:
      10.2 KB
  8. Jul 20, 2010 #7
    Its long, so you can ignore the effects at the ends presumably.

    Describe what it should look like. Again, you can picture it from far away.
  9. Jul 20, 2010 #8
    I really cant picture it ay. so for d if I cut off the ends will it be right then?
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