Homework SourseA surface of area two square metres is uniformly illuminated
A surface of area two square metres is uniformly illuminated with light of intensity 10W/m^2 and wavelength 600nm. How many photons strike the surface each second?
A surface of area two square metres is uniformly illuminated with light of intensity 10W/m^2 and wavelength 600nm. How many photons strike the surface each second?
Solution
E = nhc/lambda
E = intensity*area = 10 W/m^2 * 2 m^2 = 20W = 20 J/sec
20 = n*6.634*10^-34*3*10^8/(600*10^-9)
n = 20*600*10^-9/(6.634*10^-34*3*10^8) = 6.029*10^+19 photons per second
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