Definitions [6]
Define the work function of a metal. Give its unit.
The minimum energy needed for an electron to escape from the metal surface is called the work function of that metal. Its unit is electron volt (eV).
The phenomenon of emission of electrons from the metal surface is called "Electron Emission".
The minimum energy required by an electron to escape from the surface of a metal is called the work function (ϕ0) of that metal.
Unit: electron volt (eV).
An electron volt is the energy gained by an electron when it is accelerated through a potential difference of 1 volt.
1 eV = 1.602 × 10−19J
Give the definition of intensity of light according to quantum concept and its unit.
Intensity of light refers to the strength or brightness or amount of light produced by a specific source. Its unit is the candela (cd).
Define stopping potential.
The minimum negative potential given to the anode of a photo-cell for which the photoelectric current becomes zero is called stopping potential.
