Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

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

    Tide

    User Avatar
    Science Advisor
    Homework Helper

    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?
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook