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Homework Help: Electric Fields Problem

  1. Feb 11, 2010 #1
    A 40 Micro Coluomb test charge is placed in an electric feild produced by a 5 Coloumb charge. It expierences a 6 newton force. What is the strength of the electric feild at this point? If the test charge has a mass of 3 x 10 ^ -20 Kg, what acceleration does it expierence?

    I Think I could use the 6 newton force and divide it by the first force 5 Coloumbs to get the electric feild, and then on from their I could use a force table get the acceleration, but I am not exactly positive how to set up the Free body diagram and force table for this.

    I'm Just stuck on how to find the acceleration really
  2. jcsd
  3. Feb 11, 2010 #2


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    1. How is force on a charge related to the electric field in which this charge finds itself?
    2. 5 coulombs is a charge not a force
    3. Assuming that you know the force on the charge and the mass of the charge. What does Newton's Second Law say about the acceleration?
  4. Feb 11, 2010 #3
    oh you can use F=ma to figure out the acceleration thanks :-) also, how would you know where the first charge the 5 coluombs was in relation the the test charge?
    Last edited: Feb 11, 2010
  5. Apr 6, 2010 #4
    You can find the distance (if you really wanted to) with the definition of electric force, F - (kq1q2)/d2. You know F and the charges, and k's a constant. And distance can't be negative, so you don't have to worry about that when evaluating the square root ;)

    (hello classmate! See, I TOLD you I'd get on here!)
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