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View Full Version : BBR and Photoelectric Effect Problems: NightLight


yuvlevental
Feb26-08, 09:38 PM
1. The problem statement, all variables and given/known data
Assume that a 10-W nightlight delivers 5.9 percent of its energy in the form of visible light with a 579 nm average photon wavelength. What is the energy of this "average" photon?


2. Relevant equations
W = J*s
V*F = 3*10^8
I think...


3. The attempt at a solution
5.79E-7/3E8 = 1.93E-15
1.93E-15*10 = 1.93E-14
1.93E-14*.059= 1.1387E-15 J


So what am I doing wrong?