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Homework Help: PLEASE HELP ME. Electric Field Question

  1. Jan 19, 2005 #1
    Please help me with the following question:

    An electron (mass m = 9.11 X 10^-31 kg) is accelerated in the uniform field E (E = 1.85 X 10^4 N/C) between two parallel charged plates. The separation of the plates is 1.20cm. The electron is accelerated from rest near the negative plate and passes through a tiny hole in the positive plate. (a) With what speed does it leave the hole? (b) Show that the gravitational force can be ignored.

    I would also REALLY appreciate it if someone could direct me to a site that teaches this particular part of physics. I usually check things like this that I dont understand on www.physicsclassroom.com, but they dont teach this particular area.
  2. jcsd
  3. Jan 19, 2005 #2


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    HINT: Calculate the potential difference between the two plates and recognize that energy is conserved! :-)
  4. Jan 19, 2005 #3
  5. Jan 19, 2005 #4
    Which formula do I use for this?
  6. Jan 19, 2005 #5
    The equation is: V = ED
  7. Jan 19, 2005 #6
    After reading around a bit more, I think I figured it out.

    This is the answer I got 8,846,517 m/s. Is that even close to right?