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Homework Help: Voltage Question

  1. Apr 1, 2012 #1
    1. The problem statement, all variables and given/known data
    A 4.0μC charge is situated at the origin of an xy coordinate system. What is the potential difference between the points x=4.0m and y=2.0m because of this charge?


    2. Relevant equations

    V = k X q/r

    3. The attempt at a solution

    So i got the absolute value of the voltage to be 9.0 X 103. Howver how do you know if the voltage is negative or positive?
     
  2. jcsd
  3. Apr 1, 2012 #2

    gneill

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    Staff: Mentor

    The question asks for the potential difference, so find the potential at 4.0m and at 2.0m and then take the difference.
     
  4. Apr 1, 2012 #3
    how do i know which voltage comes first in the difference?
     
  5. Apr 1, 2012 #4

    gneill

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    Staff: Mentor

    If asked the difference between A and B, I'd write "A - B".
     
  6. Apr 1, 2012 #5
    thank you so much!
     
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