1. Not finding help here? Sign up for a free 30min 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!

Photoelectric effect

  1. Mar 20, 2010 #1
    1. The problem statement, all variables and given/known data
    What potential difference must be applied to stop the fastest photoelectrons by a nickel surface under the action of ultraviolet light of wavelength 220 nm? work function of nickel is 5.00eV.


    2. Relevant equations
    h[c]/[[tex]\lambda[/tex]] = [tex]\Phi[/tex] + eV


    3. The attempt at a solution
    h=6.6x10^-34 Js
    c=3.0x10^8 m/s
    [tex]\lambda[/tex]=200x10^-9 m
    [tex]\Phi[/tex]=5.00eV
    e=1.6x10^-19
    V=?

    [6.6x10^-34(3.0x10^8)]/[/200x10^-9] = 5.00 + 1.6x10^-19V
    9.9x10^-37 = 5.00 + 1.6x10^-19V
    9.9x10^37/5.00 = + 1.6x10^-19V
    1.98x10^37 / - 1.6x10^-19 =V
    v= 1.23x10^.18m/s

    not sure if this is right
     
    Last edited: Mar 20, 2010
  2. jcsd
  3. Mar 20, 2010 #2

    kuruman

    User Avatar
    Homework Helper
    Gold Member

    You need to convert the work function from eV to Joules before you plug it in.
     
  4. Mar 20, 2010 #3
    Also: really watch your units. As you have the equation solved... you're giving an answer in m/s... which doesn't make any sense. Carry your units along with the math... the problem is looking for a potential difference (and the solution should therefore be in volts).
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Photoelectric effect
  1. Photoelectric Effect (Replies: 2)

  2. Photoelectric effect (Replies: 6)

Loading...