In photoelectron emission, the threshold frequency is defined as the:

1.	In photoelectron emission, the threshold frequency is defined as the:
A.	minimum frequency at which field emission begins
B.	lowest frequency at which photoemission of electron starts
C.	maximum frequency at which photoemission of electron stops
D.	None of these
Answer» B. lowest frequency at which photoemission of electron starts

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In photoelectron emission, the threshold frequency is defined as the:

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