The threshold frequency is the frequency below which :
A. Photo current increases with voltage
B. Photo current decreases with voltage
C. Photo electric emission is not possible
D. Photo current is constant
Answer: Option C
Solution (By Examveda Team)
The photoelectric effect is the emission of electrons by substances, especially metals, when light falls on their surfaces. The photoelectric effect will not occur when the frequency of the incident light is less than the threshold frequency as the electrons are unable to gain sufficient energy to overcome the electrostatic barrier of the work function of the metal.This Question Belongs to General Knowledge >> Physics
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C. Diffusion of ink through the blotting
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