question_answer

If the work function of a photometal is 6.825 eV. Its threshold wavelength will be \[(c=3\times {{10}^{8}}\,m/s)\] [Pb. PET 2000; BHU 2004]

A)            1200 Å                                     

B)            1800 Å

C)            2400 Å                                     

D)            3600 Å