Sodium and copper have work functions 2.3\[eV\]and 4.5\[eV\] respectiv – McqOptions

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1.	Sodium and copper have work functions 2.3\[eV\]and 4.5\[eV\] respectively. Then the ratio of their threshold wavelengths is nearest to [AIEEE 2002]
A.	1: 2
B.	4 : 1
C.	2 : 1
D.	1 : 4
Answer» D. 1 : 4

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