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Formula Photoelectric effect Work function    Frequency    Stopping voltage    Planck's constant

Formula: Photoelectric effect
Capacitor with set stopping voltage for photoelectric effect
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Work function

Work function is the energy that must be spent to eject an electron from a solid (e.g. from a metal plate). It is usually expressed in units of "eV" (electronvolt).


Frequency of the light with which, for example, a metal plate is illuminated.

Stopping voltage

Back voltage is the voltage between two capacitor plates. This voltage is adjusted so that the electrical energy \(e \, U_{\text G} \) exactly compensates the kinetic energy of the ejected electron.

Elementary charge

Elementary charge is the charge of the electron and has the amount: $$ e = 1.602\, 176 \, 634 \, \cdot \, 10^{-19} \, \mathrm{C} $$

Planck's constant

Planck's constant is a physical constant and has the value:$$ h ~=~ 6.626 \, 070 \, 15 \, \cdot \,10^{-34} \, \mathrm{Js} $$