The work function for sodium surface is 2.0eV and that for aluminium surface is 4.2eV. The two metals are illuminated with appropriate radiations so as to cause protoemission. ThenA. Both aluminium and sodium will have the same threshold frequencyB. The threshold frequency of aluminium will be more than that of sodiumC. The threshold frequency of aluminium will be less than that of sodiumD. The threshold wavelength of aluminium will be more than that of sodium

The work function for sodium surface is 2.0eV and that for aluminium s

1.	The work function for sodium surface is 2.0eV and that for aluminium surface is 4.2eV. The two metals are illuminated with appropriate radiations so as to cause protoemission. ThenA. Both aluminium and sodium will have the same threshold frequencyB. The threshold frequency of aluminium will be more than that of sodiumC. The threshold frequency of aluminium will be less than that of sodiumD. The threshold wavelength of aluminium will be more than that of sodium
Answer» Correct Answer - B The threshold frequency for `Al` must be greater it has higher work function.

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