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Homework Help: Electric Potential (Conceptual question)

  1. Dec 11, 2008 #1
    1. The problem statement, all variables and given/known data
    To find "E" in an electrostatics problem when you are given the velocities and/or distance, you would use the formula E = Δv/d.

    Given the information below to start out with, derive the equation E = Δv/d and explain what happens to the negative signs (where do they go and why) as you continue to derive the equation.

    Given information:
    ΔEp = -ΔEk
    Δv/d = Eki - Ekf
    Δv/d = -1/2mvf^2

    2. Relevant equations
    E = Δv/d

    3. The attempt at a solution
    For me to derive this equation any further to the equation E = Δv/d I will have to somehow get rid of that negative, I was just wondering, what happens to that negative?
  2. jcsd
  3. Dec 11, 2008 #2


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    Homework Helper

    In the given problem delta v is not the change in velocity, but change in potential . Please go through the definition of electric potential at any point due to a charge.
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