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Homework Help: Magnitude of Electric Field problem

  1. Feb 20, 2008 #1
    1. The problem statement, all variables and given/known data
    If q+ve=2.01 nC, q-ve=-2.01 nC, d1=3.28 cm, and d2=6.56 cm, what is the magnitude of the electric field at the position C?

    2. Relevant equations

    E=E1 + E2 E1=kq/r E2=kq/r

    3. The attempt at a solution

    I still can't get this, any help please

    this is what i've done so far -- if u notice what im doing wrong pleaseeeeee point it out

    first, i got E from Q1 using kq/r (squared) = 1.68E7
    then i got E from Q2 using kq/r (squared) -- found r using a squared+b squared= c

    then i started on getting the x and y components of each.
    we know E from Q1 is only x component, and so x = 1.68E7 while y=0

    E2 is at an angle
    (i think i might be doing this part wrong) = sin angle = d2/r (found above) , angle is 63

    x component of E2= E2cos63
    y component of E2= E2sin63

    now i add the two x together (E1)+ (-e2) and I have the neg Y

    then i use phyth. theorm to get r in N/C

    what am i doing wrong ?

    (i then went back and unsquared all my r values for kq/rSquared into kq/r and it still dont work)
  2. jcsd
  3. Feb 20, 2008 #2
    Mabey It's just me, but I don't get the problem.
    What is "q+ve"? (I know it's a charge but what kind, I don't understand the +/- ve)
    Also, what are d1 and d2? Distances from what?
    Does the point c have a special location like any axis, or is it just any point c?
  4. Feb 20, 2008 #3
    q+ve=2.01 nC, q-ve=-2.01 nC - Sorta looks like a dipole, but I don't really understand the problem either...
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