# Doubt From Modern Physics

when work function and intensity is kept constant and frequency is increased what happens to stopping potential and saturation current ?
i’m genuinely confused with life please enlighten me

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no of photons is IA/hf now since f is increasing so no of photons gaat raha heh therefore no of electrons jo bahar aah raha heh vo bhi gaat raha heh tho saturation current gatna chahiye naa
JEE’s official solution has taken saturation current as constant why?

@Sanjay_S If frequency is constant , saturation current increases with intensity and if intensity is constant then stopping potention increases (in negative value ) with increase of frequency

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anyone?

Bro saturation current will remain same. No.of photons emitting out of a surface does depend on frequency but E=nhf (where f=frequency) and we don’t know anything about E. Therefore we cannot conclusively say that increasing f will yield a decreasing n.

When f is increased only stopping potential is affected. i.e. Stopping potential becomes increasingly negative. Intensity is the only factor that increases saturation current.

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Ok I understand your point but how is my explanation wrong ?

This one

What is IA here?

Intensity and Area subtended by beam ( not surface )

How do you know that Area subtended by the beam is a constant? It isn’t mentioned

No I checked area subtended by beam is always constant

Not sure. This is the first time I’m encountering the formula that you mentioned. Check with a trusted source and let me know.

Also, I would like to know as to where you had checked about the area being constant. Link me to somethin maybe?

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I took the Etoos Video Mock test series. The solution video will be out by tommorow will share.
No I didn’t ask anyone isnt it obvious that area is a constant term?

You’ve studied Radiation pressure right under photoelectric effect
We use this here

Lambda/c is f so IA/hf
So he said area under beam is constant the only thing which can change is I and F
So I came to a conclusion using this

Dei I’ll check with my sir later da… BOARDS!

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Lol chill chill don’t get carried away

Seshu sorry for disturbing but did you get it?