I'm having trouble seeing how electric potential energy production on a conductor follows conservation of energy.(adsbygoogle = window.adsbygoogle || []).push({});

Let's use the photoelectric effect as an example. A photon with energy E = hν strikes a conductor, ejecting a photoelectron with a maximum kinetic energy of hν - φ. Assuming the maximum kinetic energy is achieved, this leaves only φ to be transferred from the photon into the conductor.

However, we know that electrical energy follows the equation E = QV = Q^{2}/C, which implies that the electric potential energy produced on the conductor by the photoelectric effect is equal to E_{prod}= E_{fin}- E_{init}= (Q_{init}+ Q_{elec})^{2}/C - Q^{2}_{init}/C, which clearly increases with initial charge. Since φ is a constant, this implies that it is possible for E_{prod}to be greater than φ, which appears to violate conservation of energy since φ was the total amount of energy that entered the conductor.

Clearly I'm missing something. Any help would be much appreciated.

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# I Conservation of electrical energy on a conductor

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