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Homework Help: Find the surface charge density

  1. Jul 17, 2005 #1
    Helllo everyone i'm stuck. A sphereical metal satelliete 1.3m in diameter accumulates 2.4x10^-6 C of charge in one orbital revolution. Find the resulting surface charge density. This is a simple plug in chug problem i think....I know the charge and radius but i can't finda formula that works. The closest one i found was: E = [tex]\delta[/tex]/Eo; Any suggestions?
     
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  3. Jul 17, 2005 #2

    Doc Al

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    Staff: Mentor

    You have the charge. All you need is the surface area. Look up the formula for the surface area of a sphere.
     
  4. Jul 17, 2005 #3
    ohhh so charge here doesn't mean q enclosed, it means surface charge density? So i could use E = [tex]\delta[/tex]/(2piEor)
     
  5. Jul 17, 2005 #4

    Doc Al

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    Right. The problem (as you gave it) states: "Find the resulting surface charge density."

    And the most direct way to calculate surface charge density is by its definition: [surface charge]/[surface area]. So... what's the surface area of a sphere?
     
  6. Jul 17, 2005 #5
    Oh i think you misunderstood when i said, "ohhh so charge here doesn't mean q enclosed, it means surface charge density? " I was talking about, it said: "...accumulates 2.4x10^-6 C of charge in one orbital revolution." <---that charge is q not [tex]\delta[/tex] right? The surface are of a sphere is 4PIr^2. E = [tex]\delta[/tex]/(4PIr^2Eo) like that?
     
  7. Jul 17, 2005 #6
    ahhh n/m i'm retarded, i didn't even read ur post cleary, thanks i got it with ur suggestion!!
     
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