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The threshold frequency is the frequency...

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

Text Solution

Verified by Experts

The correct Answer is:
C
The photoelectric effect is the emission of electrons by substances, especially metals, when light falls on their sur faces. 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 electro- static barrier of the work func- tion of the metal.
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