Experimental setup & saturation current: photoelectric effect | Dual nature of light | Khan Academy

Let's explore how to measure the no. of photoelectrons emitted per second experimentally, in photoelectric effect. We will also draw a graph of the photocurrent vs anode potential.

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Created by Mahesh Shenoy

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[ManojKumar-xkwp]

we are increasing the potential the electrons speed also increases, since i=nq/t u are saying n becomes constant but that does not mean q/t is constant then why current is getting saturation value

[arhamdugar]

i have a question
by increasing the voltage, we have decreased the work function and increased the kinetic energy of the emitted photoelectrons so why does photocurrent become constant and does not increase as velocity of electrons will increase with increase in potential difference?

[flip]

Why does increasing the voltage increase the current here? Is it because you can treat it as a circuit and Ohm's law applies?

[halumgrr]

As we increase the voltage, the collector receives more electron per second and also they're being attracted with much greater force than before(because of more voltage), so the electrons should be received and circulating in the circuit quicker than before, shouldn't that result in higher circuit current regardless of the fact that we cannot increase the no. of electrons received per second anymore? ( therefore no thing as saturation current). What point am I missing?

[okellokennedy]

By setting up a pd (the collector being positive with respect to emitter)

[dravikumar]

Here, in saturation current topic we have seen photon ejected almost all the electrons
Then it must have efficiency like more than 90% right but why the efficiency of photoelectric effect is nearly 0.1%?

[sainidhikarthikeyan]

Actually speaking, saturation current/e gives the number of photoelectrons/sec right?

[sitcomshorts]

If electrons are collected using voltage that would result in more electron that is to say the pulling out of electron would not be impartial to light now.

[electroniciit]

what if the photoelectrons are just coming out with no kinetic energy . will the system still detect photoelectrons .