1. Limited time only! Sign up for a free 30min personal 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!

Homework Help: Electric Field problem

  1. Jan 11, 2005 #1
    A uniform electric field has a magnitude of 3.0x10^3 N/C. In a vacuum, a proton begins with a speed of 2.3x10^4 m/s and moves in the direction of this field. Find the speed of the proton after it has moved a distance of .003 m.

    I try to work out the problem with the equation F=qE to find the acceleration and plug that into a kinematics equation, but I do not have q. Can anyone help?
  2. jcsd
  3. Jan 11, 2005 #2


    User Avatar
    Science Advisor
    Gold Member

    You are told it is a proton, so it has a charge equal in magnitude to an electron (with opposite sign). 1.6*10^-19 C, I think. You should look it up in your textbook.
  4. Jan 11, 2005 #3
    ah got it! I actually tried that just before I posted on here except I left the negative sign on the charge. Thanks alot!
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook