Physics · Dawn of Modern Physics
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If sunlight is incident on the photocell, the number of electrons emitted from the surface of the cell increases with the:
- A
Increase of light frequency
- B
Increase of light intensity
- C
Decrease of light frequency
- D
Decrease of light intensity
As the frequency increases beyond the threshold, the ejected electrons simply move faster. An increase in the intensity of incoming light that is above the threshold frequency causes the number of electrons that are ejected to increase, but they do not travel any faster.
Increase of light frequency: frequency of light is related to the energy of photon and if the frequency of photon increase then the energy with thich photon emits is increase and not number of electrons .
Increase of light intensity :
With the increase in intrensity of light the number of electrons emitting increase because the energy of photon remain same but with the quantity of photon striking increase as its intensity increases so it ejects more electrons from photocell.
Decrease of light frequency :
With decrease in frequency of light the energy with which photon eject decrease but it dosen't effect the number of electrons ejecting from the photocell.
Decrease of light intensity:
With the decrease in intensity of light the number of electrons ejecting from surface of photocell decrease .
Tagged under Physics · Dawn of Modern Physics · 2018