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Electric Field Problem

  1. Feb 4, 2008 #1
    [SOLVED] Electric Field Problem

    1. The problem statement, all variables and given/known data

    At some instant the velocity components of an electron moving between two charged parallel plates are Vx = 1.5E5 m/s and vy = 1.8E3 m/s. Suppose that the electric field between the plates is given by E = (140 N/C) j.

    (a) What is the electron's acceleration in the field?

    (b) What is the electron's velocity when its x coordinate has changed by 3.6 cm?

    2. Relevant equations
    I got the first answer doing ---- a = (e/m) E.

    so the answer came out to be -2.45E13.

    For b. you have to find the x portion for the velocity and the y portion of the veloctity

    i found the x, it just stays the same and for the y:


    D = v0^2 - v^2 / (2a)

    2aD = V0^2 - V^2

    V = sqrt(v0^2 + 2aD)

    3. The attempt at a solution
    V = sqrt(v0^2 + 2aD)

    Please help
  2. jcsd
  3. Feb 4, 2008 #2

    Shooting Star

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    Homework Helper

    Find the time 't' for the x to change by 3.6 cm, which is easy since vx is constant.

    For motion in y dircn, initial speed v_yi is given, the accn in y dircn you know, and so apply v_yf = v_yi + at.
  4. Feb 4, 2008 #3
    thanx a lot for helping me out

    it worked!!!
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