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Homework Help: Parallel Plates

  1. Apr 11, 2008 #1
    1. The problem statement, all variables and given/known data

    Two oppositely charged parallel plates, 13.0 cm apart, have a uniform electric
    field between them. Vb − Va = +25.0 V. An electron with a mass of
    9.11 × 10−31 kg and a charge of −1.60 × 10−19 C is released from rest at plate a.
    Calculate the speed of the electron when it reaches plate b.

    | |
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    a b



    3. The attempt at a solution

    E=V/d = 25/.13 = 192.3J

    I also need you need to find accel. but im not sure how.

    please help, thanks
     
  2. jcsd
  3. Apr 11, 2008 #2

    nrqed

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    Science Advisor
    Homework Helper
    Gold Member


    What is the equation for the electric force on a charge in an electric field?
     
  4. Apr 11, 2008 #3
    E=kq/d^2
     
  5. Apr 11, 2008 #4

    pam

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    Use conservation of energy.
     
  6. Apr 11, 2008 #5
    oh, and the answer is

    2.96 × 10^6 m/s
     
  7. Apr 11, 2008 #6
    Vq=1/2mv^2


    But im still getting the wrong answer
     
    Last edited: Apr 11, 2008
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