1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

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:

    Kinematics:

    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

    User Avatar
    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!!!
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?