Quantity of photons emitted from a sodium lamp

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SUMMARY

A 100 W sodium lamp emits photons at a wavelength of 589 nm, with 50% of its energy dedicated to light production. This results in an effective power output of 50 W for light emission. The energy of each photon can be calculated using the formula E = hc/λ, where h is Planck's constant and c is the speed of light. By determining the total energy emitted per second and dividing it by the energy per photon, one can calculate the total number of photons emitted per second.

PREREQUISITES
  • Understanding of Planck's constant (h) and the speed of light (c)
  • Familiarity with the energy-wavelength relationship for photons
  • Basic knowledge of power calculations in electrical systems
  • Ability to perform unit conversions (e.g., watts to joules)
NEXT STEPS
  • Calculate the energy of a single photon at 589 nm using E = hc/λ
  • Determine the total energy output of the sodium lamp per second
  • Calculate the number of photons emitted per second from the lamp
  • Explore the implications of photon emission in practical applications, such as lighting efficiency
USEFUL FOR

Physicists, electrical engineers, and anyone interested in photonics or the efficiency of lighting technologies.

Eivind
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How many photons is sendt out per second from a 100 W natrium lamp, which gives a wawelenght of 589 nm(if 50% of the energi goes to the creation of light)?

I think I have to use photo elektric effect, but how?

Hints, anyone?
 
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You don't have to use the photoelectric effect. Each photon carries an energy determined by its wavelength. If you know the energy the lamp dissipates as light (per second) you can calculate how much photons that amounts to (per second).
 

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