We see in photoelectric effect by increasing frequency the K.E of photoelectrons increases.
By the definition of current=charge/time
If velocity of electrons increases then time will be less then current should increase then why current remains constant.?
Dear Qasim Anwar M Anwar ,
In the photoelectric effect , the generated electrons and holes depends only on the the intensity of the incident light. The alternation rate in the intensity of the incident light has only effect on the current when the this alternation rate is greater than the response rate of the photoconductor.
I would like that you refer to the elementary book: Book Electronic Devices
Best wishes
Dear Qasim Anwar M Anwar ,
the photoelectric current is the number of charges produced due to the photo effect per time interval. The amount (or number) of charges is independent on the kinetic photo electron's energy, which is the excess energy when the photon energy is exceeding the workfunction.
So increasing the photon energy, which is proportional to the photon frequency of the light, will only alter the kinetic energy (or speed) of the photo electrons but not their numbers, when further secondary excitations and photo effects via the primary photo electrons not are regarded.
The time arising in your definition above is due to the photon intensity ( = number of photons per time ) which is impinging onto your sample.
You have the photoelectron current being proportional to the photon intensity.
PhotoelectronCurrent = Y * PhotonIntensity. The proportionality constant Y called the photoelectron yield.
Dear Qasim Anwar M Anwar ,
In the photoelectric effect , the generated electrons and holes depends only on the the intensity of the incident light. The alternation rate in the intensity of the incident light has only effect on the current when the this alternation rate is greater than the response rate of the photoconductor.
I would like that you refer to the elementary book: Book Electronic Devices
Best wishes
The current is the charge that crosses a given surface per unit of time. If this surface is on the surface of the cell, this charge is proportional to the number of ejected electron per unit time in this region of the cell, and then doesn't depend on their velocity. The electrons arrive faster, but there is no more of them.
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