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Homework Help: Find capacitance (calculus)

  1. Mar 30, 2010 #1
    1. The problem statement, all variables and given/known data

    Determine the capacitance of two conducting plates facing each other at an angle as shown (in link) . Plate A and B have dimensions of 10x20 cm and 10x (20sec30) (angles in degrees)

    2. Relevant equations
    C=( [tex]\epsilon[/tex] A)/d

    3. The attempt at a solution
    not quite sure can someone help me get the ball rolling or the floor moving

    Attached Files:

  2. jcsd
  3. Mar 30, 2010 #2


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    Homework Helper

    If you take one strip of the plate of width dx and length L.
    The capacity of that strip is given by
    ΔC = εο*L*dx/(d + d')
    From the figure write down d' in terms of x and θ.
    Find the integration to get the capacitance C.
  4. Mar 31, 2010 #3
    What are you using for d' ?
  5. Mar 31, 2010 #4


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    d' is the variance distance of the slanted plate from the horizontal line.
    In the problem, numerical values are not correct.
    One end of the slanted plate is 1 mm from the top plate,. And the other end is 0.1 mm from the top plate. So tan θ = 0.9 mm/0.1 mm which is not equal to tan(30)
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