Light of wavelength 4000 \[\overset{\text{o}}{\mathop{\text{A}}}\,\] i – McqOptions

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1.	Light of wavelength 4000 \[\overset{\text{o}}{\mathop{\text{A}}}\,\] is incident on a sodium surface for which the threshold wave length of photo electrons is 5420 \[\overset{\text{o}}{\mathop{\text{A}}}\,\]. The work function of sodium is
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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