The predominant wavelength emitted by an ultraviolet lamp is 248 nm. If the total power emitted at this wavelength is 14.0 W, how many photons are emitted per second?
Thank you in advance if you can help!!
Thank you in advance if you can help!!
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The energy of a photon Ep=h*c/L where h=Planck's constant and L is wavelength
Total energy in 1s
E=P*t=14*1 = 14J
N_photons=E/Ep=14*248*10^-9/(3*10^8 * 6.6*10^-34) =~1.75*10^19
Total energy in 1s
E=P*t=14*1 = 14J
N_photons=E/Ep=14*248*10^-9/(3*10^8 * 6.6*10^-34) =~1.75*10^19
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Figure out how many Joules are emitted in a second.
Figure out how many Joules are in a photon.
The first number divided by the second number is the number of photons in a second.
How many Joules are emitted? 14.0 W means 14 J/sec.
How many Joules in a photon? E = hc/lambda where lambda = wavelength in meters.
Figure out how many Joules are in a photon.
The first number divided by the second number is the number of photons in a second.
How many Joules are emitted? 14.0 W means 14 J/sec.
How many Joules in a photon? E = hc/lambda where lambda = wavelength in meters.