Photoelectric Equation - SI unit question

AI Thread Summary
The discussion centers on the photoelectric equation eV0 = hf - w0 and the need to express it in the linear form y = mx + C for graphing stopping voltage against frequency. The user successfully reformulates the equation to identify V0 as the dependent variable, with h/e as the gradient and -w0/e as the y-intercept. The main confusion arises regarding the SI units of h/e and w0/e, with references to Planck's constant (h) in joule-seconds (Js) and the work function energy in electronvolts (eV). Clarification is sought on how to express these units consistently, emphasizing that eV is equivalent to joules (J). The discussion highlights the importance of understanding unit conversions in the context of the photoelectric effect.
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Homework Statement


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 ?

Homework Equations

The Attempt at a Solution

 
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##E=hf##. What are the units of ##h##?
What are the units of work function energy?
 
Work function is eV but Planck constant has Js , ev/s
 
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.
 
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