Formula to find maximum kinetic energy?

AI Thread Summary
The discussion centers on calculating the maximum kinetic energy of a particle using the work function and the wavelength of incident UV light. The relevant equations include E=hf and E=hc/λ, with the maximum kinetic energy expressed as KE=hc/λ – Φ, where Φ is the work function. The user initially struggles with the concept but realizes that the work function represents the energy needed to release the particle from the surface, with the remaining energy contributing to kinetic energy. This clarification simplifies the understanding of the problem. The conversation highlights the importance of grasping the relationship between photon energy and kinetic energy in photoelectric effects.
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Homework Statement



Work Function=3.6 EV
Wavelength=250nm, UV
Maximum kinetic energy=?


Homework Equations



E=hf

Formulas from mark scheme:
E = hc/λ
hc/λ – Φ

The Attempt at a Solution



I had a vague idea of what to do, I just didn't understand why in the second formula from the mark scheme the work function is taken away from E
 
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I haven't worked with this for a while, but isn't it just the conservation of energy? You are using the energy of the incident 250 nm photon to pull the particle from the surface (the work function) and the rest of the photon's energy goes into kinetic energy:
KE=hc/λ – Φ.
 
It's so much simpler now that you've put it that way. Thank you so much! :'D
 
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