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Homework Help: Initial Accel of a Particle

  1. Jan 31, 2006 #1
    im stuck on this question if any1 could help i'd appreciate it. A particle of mass 30 g and charge 26 uC is released ffrom rest when it is 59 cm from a second particle of charge -11 uC. The question ask for the initial acceleration of the 30 g particle.
     
  2. jcsd
  3. Jan 31, 2006 #2
    To start with....

    Try working out the forces being exerted by the particles.
     
  4. Jan 31, 2006 #3

    Doc Al

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    Staff: Mentor

    What force acts on the particle? (Hint: Consider Coulomb's law)
     
  5. Jan 31, 2006 #4
    so i work out the forces using coulombs law, but then how do u find acceleration in m/s?
     
  6. Jan 31, 2006 #5

    Doc Al

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    Use Newton's 2nd law. (Acceleration has units of m/s^2, not m/s.)
     
  7. Jan 31, 2006 #6
    heres what i got can u tell me if its on the right track

    F = k (Q1) (Q2) / r^2

    F = (9.0 x 10^9) (26uC) (-11uC) / (0.59m)^2


    = -7.39 x 10^13 N
     
    Last edited: Jan 31, 2006
  8. Jan 31, 2006 #7

    Doc Al

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    Realize that [itex]\mu \mbox{C}[/itex] means micro-Coulombs: 1 [itex]\mu \mbox{C} = 10^{-6} \mbox{C}[/itex].
     
  9. Jan 31, 2006 #8
    when dividing by the mass do i have to change grams to kg?
     
  10. Jan 31, 2006 #9
    Think of the units that make up a Newton and make sure you use the same
     
  11. Jan 31, 2006 #10
    thank u guys for ur help
     
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