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Question
What is photoelectri effect ? Defin (i) Stopping potential (ii) Photoelectric work function.
Solution
The phoenomenon of emission of electron by certain substance (metal), when it is exposed to radiation of suitable frequencies is called photo electric effect. Thus in photoelectric effect emitted electrons are called
photoelectrons.
(i) Stopping -potential : The minimum negative potential given to the plate for which photo electric current stop or become zero.
(ii) Photo electric work function : The minimum energy required to remove electron from a given surface is called photo electric work function
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