A metallic surface with work function of 2 eV, on heating to a tempera – McqOptions

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1.	A metallic surface with work function of 2 eV, on heating to a temperature of 800 K gives an emission current of 1 mA. If another metallic surface having the same surface area, same emission constant but work function 4 eV is heated to a temperature of 1600 K, then the emission current will be
A.	1 mA
B.	2 mA
C.	4 mA
D.	None of these
Answer» D. None of these

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