Maximum photocurrent in photoelectric effect

J-F
I would like to know why, experimentaly, there is a difference between the maximum photocurrent with a yellow illumination (lambda = 580 nm) and other colors with a lower wavelenght like green or blue, respectively 546 and 404 nm. According to the theory, the max photocurrent does not depend of the wavelenght of the illumination

Thanks
 
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Originally posted by J-F
According to the theory, the max photocurrent does not depend of the wavelenght of the illumination
Don't know what theory you refer to, but it's certainly not quantum theory. Because quantum theory states that longer-wavelength radiation consists of photons with lower energy. Which thus have a smaller chance to kick an electron out of the photoconductor's surface. See here:
http://www.colorado.edu/physics/2000/quantumzone/photoelectric.html
 
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for your question. The maximum photocurrent in the photoelectric effect is determined by the energy of the incident photons, not the wavelength. According to the theory, the maximum photocurrent should not depend on the wavelength of the illumination. However, in experiments, we often see a difference in the maximum photocurrent for different colors of light.

This can be explained by the fact that different colors of light have different energies. For example, yellow light has a longer wavelength and therefore a lower energy than green or blue light. This means that yellow light will not be able to eject electrons with as much energy as green or blue light, resulting in a lower maximum photocurrent.

Additionally, the materials used in the experiment can also play a role in the difference in maximum photocurrent. Some materials may have a higher sensitivity to certain wavelengths of light, resulting in a higher maximum photocurrent for those colors.

It is also important to note that the maximum photocurrent is not the only factor that determines the efficiency of the photoelectric effect. Other factors such as the intensity of the light and the properties of the material can also affect the overall efficiency.

In conclusion, while the theory states that the maximum photocurrent should not depend on the wavelength of the illumination, in practice, there can be variations due to the energy of the incident photons and the properties of the material used. It is important to carefully consider all factors when conducting experiments and interpreting results in the photoelectric effect.
 
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