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Homework Help: Help needed: Charge on 2 spherical conductors connected with a cylindrical conducor

  1. Nov 21, 2008 #1
    1. The problem statement, all variables and given/known data

    2 conducting spheres with radii 2 & 3m are connected with a conducting rod of thickness 0.1m & lenght 0.5m. 500C charge is put on the 2m radius sphere.
    Find the amount of charge on each sphere & on the rod.

    2. Relevant equations


    3. The attempt at a solution

    By conservation of charges: Q1 + Q2 + Q3 = 500 ... (1); Q1 of rod & Q2 & Q3 of 2m & 3m radii spheres respectively.

    As charges are uniformly distributed we have: [tex]\sigma[/tex]1 = [tex]\sigma[/tex]2 = [tex]\sigma[/tex]3

    so Q1/A1 = Q2/A2 = Q3/A3 ... (2)



    here i got stuck & don;t know how to continue. i know that i need to find 3 equations with 3 unkowns & solve the system, but im not seeing these equation except for (1) & probably i have to use parts of (2).

    could someone help plz. thx
     
  2. jcsd
  3. Nov 22, 2008 #2
    Re: help needed: Charge on 2 spherical conductors connected with a cylindrical conduc

    you have three equations, (1) and two equations in (2). Q_1/A_1 = Q_2/A_2 and Q_2/A_2 = Q_3/A_3.
     
  4. Nov 22, 2008 #3
    Re: help needed: Charge on 2 spherical conductors connected with a cylindrical conduc

    thx 4 the help
     
  5. Nov 22, 2008 #4
    Re: help needed: Charge on 2 spherical conductors connected with a cylindrical conduc

    Can you justify this?
     
  6. Nov 23, 2008 #5
    Re: help needed: Charge on 2 spherical conductors connected with a cylindrical conduc

    coz charges on conductors tend to uniformly distribute them selves. isn't it?
     
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