Light of wavelength 4000 Å is incident on a sodium surface for which – McqOptions

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1.	Light of wavelength 4000 Å is incident on a sodium surface for which the threshold wave length of photo ? electrons is 5420 Å. The work function of sodium is [MP PMT 1993; Pb. PMT 2002]
A.	4.58 eV
B.	2.29 eV
C.	1.14 eV
D.	0.57 eV
Answer» C. 1.14 eV

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