Physics-
General
Easy
Question
Photoelectric emission is observed from a metallic surface for frequencies 
and 
of the incident light rays 
. If the maximum values of kinetic energy of the photoelectrons emitted in the two cases are in the ratio of 
, then the threshold frequency of the metallic surface is
The correct answer is:
By using 
….(i)
And 
….(ii)
, Hence 
.
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