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: Work performed on a proton between two charged plates

  1. Feb 4, 2010 #1
    1. The problem statement, all variables and given/known data
    A set of parallel conducting plates are seperated by .05 m. When the plates are fully charged to a potential difference of 20 V, how much work would have to be performed to move a proton from the negatively charged plate to the positively charged plate?

    My second question would be, is it negative work because its moving a positive charge towards the postive plate?


    2. Relevant equations
    V = k*q/r
    We = qV
    V = Ed



    3. The attempt at a solution
    20 * ? Im sorry i just dont understand this concept that well
     
  2. jcsd
  3. Feb 4, 2010 #2

    rl.bhat

    User Avatar
    Homework Helper

    Work = F*d*cosθ.
    Here force on the proton is E*q away from the positive plate.
    Proton is moving towards the +ve plate. So θ = 180 degrees.
    With these information find W.
     
  4. Feb 4, 2010 #3
    Wait...so I understand it being 180 degrees...but i do i need to use the protons charge as 1.6*10^-16 to find the force applied first?
     
  5. Feb 4, 2010 #4

    rl.bhat

    User Avatar
    Homework Helper

    Yes.
    The final formula will be
    W = V*q*cosθ.
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook