Photoelectric Equation - SI unit question

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SUMMARY

The discussion centers on the photoelectric equation, specifically the relationship between stopping voltage (V0), frequency (f), Planck's constant (h), and the work function (w0). The equation is rearranged to V0 = (h/e) * f - (w0/e), where V0 represents stopping voltage, h is Planck's constant, e is the electron charge, and w0 is the threshold frequency. The user seeks clarification on the SI units for h/e and w0/e, noting that Planck's constant has units of Joules-seconds (Js) and the work function is expressed in electronvolts (eV), which is equivalent to Joules (J).

PREREQUISITES
  • Understanding of the photoelectric effect and its equations
  • Familiarity with Planck's constant (h) and its units (Js)
  • Knowledge of the electron charge (e) and its role in physics
  • Basic grasp of energy units, specifically Joules (J) and electronvolts (eV)
NEXT STEPS
  • Research the derivation and implications of the photoelectric equation
  • Learn about the relationship between energy units: Joules and electronvolts
  • Explore the significance of threshold frequency in the photoelectric effect
  • Investigate the concept of stopping voltage and its measurement in experiments
USEFUL FOR

Students studying physics, particularly those focusing on quantum mechanics and the photoelectric effect, as well as educators looking to clarify concepts related to energy units and their applications in experimental physics.

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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

 
Physics news on Phys.org
##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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