A Sheet Of Silver Is Illuminated By Monochromatic Ultraviolet Radiation Of Wavelength 1810 Å. What Is The Maximum Energy Of The Emitted Electrons? The Threshold Wavelength For Silver Is 2640 Å. 

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A sheet of silver is illuminated by monochromatic ultraviolet radiation of wavelength 1810 Å. What is the maximum energy of the emitted electrons? The threshold wavelength for silver is 2640 Å. 


Correct option is

2.16 eV

If v be the frequency of radiation illuminating the surface and v0 the threshold frequency, then according to Einstein’s photoelectric equation, the maximum kinetic energy of the emitted electrons is 


If  be the wavelength of the incident light and , the threshold wavelength, then   


Substituting the given values of hc and . We have 






             = 2.16 eV.   



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