Questioning photoelectric effect theory

AI Thread Summary
The discussion centers on an experiment investigating the photoelectric effect using various light sources, revealing inconsistencies in retarding potentials and photocurrents. While the theory states that only the frequency of incident light affects electron emission energy, the intensity of different light sources can influence the number of emitted electrons, leading to varying currents. Additionally, the surface properties of the metal, such as differing work functions, may also contribute to these discrepancies. The experiment highlights the complexity of the photoelectric effect and suggests that further exploration is necessary to understand the observed variations. Overall, the findings prompt a reevaluation of factors influencing photocurrent beyond just frequency.
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I'm working on a lab where I used LEDs of different wavelenths to record photocurrent they create when striking a metal. Using this data, i was able to find an equation relating the wavelength of the incident light to the current that is produced.
My problem is that when I repeated the experiment with different light sources (HeNe Laser, Hg lamp), the retarding potentials did not fit with the data from the LED's. The photoelectric effect says that the only thing that matters in the incident light is its frequency, because things like intensity are irrelevant. So I don't see why different light sources should create different currents. I don't know if what I said made any sense, but can anyone help me out here? Basically I'm asking if there are any other factors that would effect the current produced through the photoelectric effect other than frequency. I hope someone out there can help me out. thanks
 
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moonman said:
The photoelectric effect says that the only thing that matters in the incident light is its frequency, because things like intensity are irrelevant.
Right and wrong.. the retarded potential is related to its frequency only, but the current is affected by its intensity,

moonman said:
My problem is that when I repeated the experiment with different light sources (HeNe Laser, Hg lamp), the retarding potentials did not fit with the data from the LED's.
different light sources has different frequence.. for example.. a red light has a lower frequence than a blue light.. surely you won't get a same result using different light source..

moonman said:
So I don't see why different light sources should create different currents
different light source not only have different frequency (color), their intensity (strength) varies, too..
 
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The photoelectric effect theory is a fundamental concept in physics that explains how light can cause the emission of electrons from a metal surface. It states that the energy of the incident light (determined by its frequency) is responsible for the energy of the emitted electrons, while the intensity of the light does not affect this process.

Based on your experiment, it seems that you have found an equation relating the wavelength of the incident light to the current produced in the photoelectric effect. However, you have noticed that this equation does not hold true for all light sources, as the retarding potentials did not fit with the data from the LED's when using different light sources like a HeNe laser or Hg lamp.

This discrepancy raises an important question about the photoelectric effect theory. Are there other factors that could affect the current produced in the photoelectric effect, besides the frequency of the incident light?

One possible explanation for this inconsistency could be the different intensities of the light sources. While the photoelectric effect theory states that the intensity of the light does not affect the energy of the emitted electrons, it could still affect the number of electrons that are emitted. Therefore, it is possible that the different light sources used in your experiment had varying intensities, leading to different currents being produced.

Another factor that could potentially affect the current in the photoelectric effect is the surface properties of the metal being used. Different metals have different work functions, which is the minimum energy required to remove an electron from the surface of the metal. This could also contribute to the varying currents observed in your experiment.

In conclusion, while the photoelectric effect theory is a well-established concept, there may be other factors at play that could affect the current produced in the photoelectric effect. Further experimentation and analysis may be needed to fully understand the discrepancy you have observed in your experiment.
 
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