04M.7 Imagine a model where electromagnetic radiation consists of photons but ea
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04M.7 Imagine a model where electromagnetic radiation consists of photons but each photon carries a fixed amount of energy, say, 4 eV, independent of frequency. This "fixed energy photon" (FEP) model is different than the normal photon model in that an FEP photon's energy does not depend on wavelength. How would this model contradict the expectations of a pure wave model for the photoeled- tric effect (or would it)? Would it be consistent with the photoelectric effect results actually observed (see section Q4.5)? Explain by going through each of the five listed predictions and five results and discuss whether the FEP model is consistent with each.Explanation / Answer
A pure wave model expects that when a material is hit with a high intensity wave, the energy of the electron emitted would be high. This is because, according to wave theory, the energy of a wave is proportional to intensity. So it appers resonable to expect higher energy electrons to be emitted in this case.
FEP -- Photon has fixed energy independent of frequency, contradicts with Wave model. A photon model is a particle based model in the sense that one photon is assumed to be responsible for emission of an electron. So in this case, if the intensity of the photons are increased, i.e. if the metal is bombarded with more photons per min or per unit area, it only affects the no. of electrons emitted by the metal but not the energy of each emitted electron (remember photon here has a fixed constant energy).
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Section Q4.5 not provided. But based on general experimental results of photoelectric effect, FEP is not consistent with experimental observations.
Experimentally, every metal has a threshold frequency, radiations below threshold frequency doesn't result in any photoelectric effect (no electrons are emitted) implying that those radiations doesn't have enough energy to kick an electron out of the metal. This fact would not be accounted for by FEP as it has fixed energy content.
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