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Voltages in Photoelectric Circuits

  1. Nov 21, 2009 #1
    In the photoelectric effect, if you have a frequency above the threshold frequency, electrons are ejected with greater kinetic energy, but the voltage and current of a circuit using the photoelectric effect is the same. If electrons have a greater Ek, they would have a greater speed, and so if they begin travelling through the circuit’s wire with a greater speed, more electrons would be travelling through per second, so current would be higher, and so would voltage; V= IR. But, as above, this is not the case. Is this because all the additional kinetic energy is used up when the electrons enter the wire?

    Then again, if they did enter with more energy, the extent of the conversion of potential energy to kinetic through the wire would still be the same as with electrons of lower kinetic energy, so voltage should be the same. However this conflicts with the idea that the electrons travel faster, leading to a higher current and voltage.

    I am quite confused. Please help :)
  2. jcsd
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