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Homework Help: Coulomb's Law Question

  1. Jan 7, 2010 #1
    1. The problem statement, all variables and given/known data

    I have physics homework and i dont quite seem to understand the question:
    Two objects ( X and Y ) are placed at a distance of .800m from each other. The charge on X is 6.65000x10^-6 C and Y is 7.73000x10^-6. What is the value of electrical force (in Newtons) between the two objects? Answer accurate to the fourth decimal place.

    2. Relevant equations

    i think the equation is F=kxQ1xQ2/d^2, but dont know how to solve for Q1 or Q2..and is K 9.0x10^9?
    ive tried reading the info. they provide us over and over but still dont seem to get how to solve it
    3. The attempt at a solution
    :cry: i know im a noob but please help lol
    thank you
    Last edited: Jan 7, 2010
  2. jcsd
  3. Jan 7, 2010 #2
    Q1 and Q2 are the charges on the objects, d is the distance between the objects, and k is Coulomb's constant
  4. Jan 7, 2010 #3
    but the thing is i dont know where to start..
    Last edited: Jan 7, 2010
  5. Jan 7, 2010 #4
    They give you all of those values, except for k which you can look up. Unless I'm missing something, all you have to do is plug them into the equation to get the force.
  6. Jan 7, 2010 #5
    how do i get values of k, q1, and q2 in units of Coulomb?
    oh wait they give it to us in C
  7. Jan 7, 2010 #6
    oh ok..let me try that..ive tried plugging in over and over..but couldnt get the answer..
    Last edited: Jan 7, 2010
  8. Jan 7, 2010 #7
    Yes i got it..thanks lol
    Last edited: Jan 7, 2010
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