Given energy, calculate electrons emitted

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SUMMARY

The discussion centers on calculating the maximum number of electrons emitted from cesium metal when exposed to a burst of light with a total energy of 1.16 µJ. The relevant equations include E=hv, where E is energy, h is Planck's constant, and v is frequency, as well as v=c/λ, where c is the speed of light and λ is wavelength. The critical frequency for electron emission from cesium is 4.60 x 1014 s-1. Given the total energy, the maximum number of photons can be determined, which in turn allows for the calculation of the number of emitted electrons.

PREREQUISITES
  • Understanding of Planck's constant (h = 6.626 x 10-34 J·s)
  • Knowledge of the speed of light (c = 3.00 x 108 m/s)
  • Familiarity with the photoelectric effect and its threshold frequency
  • Ability to perform calculations involving energy, frequency, and wavelength
NEXT STEPS
  • Calculate the number of photons in a burst of light using the formula E=nh, where n is the number of photons.
  • Explore the photoelectric effect in detail, focusing on the relationship between photon energy and electron emission.
  • Investigate the effects of varying light frequencies on electron emission rates from different metals.
  • Learn about the implications of photon energy distribution in practical applications such as photovoltaic cells.
USEFUL FOR

This discussion is beneficial for physics students, educators, and anyone interested in the principles of the photoelectric effect and its applications in modern technology.

ill
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Homework Statement


What is the maximum number of electrons that can be freed by a burst of light whose total energy is 1.16 µJ?


Homework Equations


E=hv
v=c/\lambda


The Attempt at a Solution


I have no problem calculating frequencies and wavelengths, my issue is how can I use these numbers to relate to number of electrons emitted. Our book tells us that light with a frequency of 4.60X10^14 s^-1 or greater will cause cesium metal to emit electrons...the above frequency comes out to 1.75X10^27 meaning it will emit electrons...what I need is some equation that relates electron emission to any of the aforementioned quantities I can find.
 
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Undoubtedly, the 1.16 uJ is not concentrated in a single photon; it's spread out over many photons. What frequency should the photons be so that they can liberate the maximum number of electrons?
 

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