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 Equation - SI unit question

  1. Apr 4, 2015 #1
    1. The problem statement, all variables and given/known data
    I am trying to plot a graph of stopping voltage against frequency

    The given equation is eV0 = hf - w0

    So i need to change it to the form of y = mx + C in order to plot this graph

    V0 = h*f/e - w0/e

    V0 = h/e * f - w0/e -- > V0 = y , m(gradient) = h/e , x= f and -w0/e = C (y intercept)

    V0 is the stopping voltage , h is Planck constant , e is the electron constant , W0 is the threshold frequency

    Now I am confused what SI unit does h/e has and w0/e ?

    2. Relevant equations


    3. The attempt at a solution
     
  2. jcsd
  3. Apr 4, 2015 #2
    ##E=hf##. What are the units of ##h##?
    What are the units of work function energy?
     
  4. Apr 4, 2015 #3
    Work function is eV but Planck constant has Js , ev/s
     
  5. Apr 4, 2015 #4
    But eV is equivalent to J right? Can you represent J in terms of SI units?
    EDIT: Remember that the work function energy is also given by an identical equation, ##φ=hf_0##, but we instead use the threshold frequency. Numbers play no role in determining the units for an equation.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted



Similar Discussions: Photoelectric Equation - SI unit question
Loading...