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: Velocity and momemtum of 10 Mev Electron

  1. Sep 22, 2008 #1
    1. The problem statement, all variables and given/known data

    Find the velocit y and momentum of an electron (rest mass of 0.511MeV) with a
    kinet ic energy of 10.0 MeV.

    3. The attempt at a solution

    The momentum I calculate using sqrt(2KEm) is giving me a V larger than the speed of light. This can't be true.

    If I try
    Rest E + KE = sqrt (m2c4 - p2c2) it gives me a negative root.
  2. jcsd
  3. Sep 22, 2008 #2
    Nevermind, I figured it out.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook