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Photoelectric effect


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In an experiment to study photocurrent( cathode ray tube?..)..connecred to a battery ..let us consider 2 cases

CASE 1

----a particular matallic emmitter is taken( work function = 4 ev)..a suitable frequency of light is made to fall(energy = 6 ev say..)..intensity being constant(say 3 electrons r emmitted).. and no potential is applied...

the energy of the electrons will be

2 ev ,1.9 ev, 2.1ev say..( theoritically all electrons hav energy = 2ev)..

CASE 2

----now keeping all as constants except potential wch is made negative( say 1 v >> stopping potential)..then energies of the electrons changes to---

...1 ev, 0.9 ev and 1.1 ev..

now my question is...whether tje current in the circuit changes?..if so how?..is it too neglogible?...

 

if the current changes then if the negative potential of 1 v is also kept constan and suppose the frequency is increased ...to say 12 ev..the enrgies of the electrons increases beyond 2 ev...now does the current increase?....

i hav referred many books wch say that negative potential effects the current but frequency doesnt,. once it is above the threshold level....pls clarify ..thanx...

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