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Homework Help: How to find the force of particles

  1. Jan 22, 2009 #1
    1. The problem statement, all variables and given/known data

    A positive and a negative charge, each of magnitude 1.9 multiplied by 10^-5 C, are separated by a distance of 11 cm. Find the force on each of the particles.


    2. Relevant equations

    F = kq^2/r^2
    r = sqrt(kq1q2/F)


    3. The attempt at a solution
    i'm not sure which numbers are placed where in each equation :(
     
  2. jcsd
  3. Jan 22, 2009 #2

    Hootenanny

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    Can you start by explaining what each of the symbols in the first equation mean?
     
  4. Jan 22, 2009 #3
    r stands for culomb's law(?), and i'm not quite sure about the others..
     
  5. Jan 22, 2009 #4
    r stands for radius which is the distance between the two charges.
    k is the columbs constant = 9x10^9
    q represents the charges. We actually ignore if its positive or negative at this point so we can say q^2
    normally it would be (q1)(q2) / r^2





    A positive and a negative charge, each of magnitude 1.9 multiplied by 10^-5 C, are separated by a distance of 11 cm. Find the force on each of the particles.

    F = kq^2/r^2 = (9 x 10^9) [(1.9 x 10^-5)^2 / (.11 m)^2)]

    that should be the force of attraction between the two
    so the force on one of the charges should point in the direction of the other charge
    the force on the other charge should point towards the first charge. They should
    both be of equal value other than positive and negative.
     
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