Ultraviolet light of wavelength 2271 Å from a 100 W mercury source irradiates a photo-cell made of molybdenum metal. If the stopping potential is -1.3 V, estimate the work function of the metal. How would the photo-cell respond to a high intensity (~10^(5) W m^(2)) red light of wavelength 6328 Å produced by a He-Ne laser ?

Ultraviolet light of wavelength 2271 Å from a 100 W mercury source ir

1.	Ultraviolet light of wavelength 2271 Å from a 100 W mercury source irradiates a photo-cell made of molybdenum metal. If the stopping potential is -1.3 V, estimate the work function of the metal. How would the photo-cell respond to a high intensity (~10^(5) W m^(2)) red light of wavelength 6328 Å produced by a He-Ne laser ?
Answer» SOLUTION :`phi_(0)=hv-eV_(0)=6.7xx10^(-19)J=4.2eV,v_(0)=(phi_(0))/(h)=1.0xx10^(15)HZ, lambda=6328Å` CORRESPONDS to `v=4.7xx10^(14)Hz lt v_(0)`. The photo - CELL will not respond howsoever high be the intensity of laster LIGHT.

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