Use Einstein photoelectric equation to explain Why for a particular metal electrons are emitted only when the frequency of the incident radiation is greater than a certain value?

The photoelectric effect occurs when photons with sufficient energy strike a metal surface, causing electrons to be emitted. According to the Einstein photoelectric equation, the energy of the emitted electron is equal to the energy of the incident photon minus the work function of the metal. Therefore, only photons with energy greater than the work function of the metal can overcome the binding energy of the electrons and cause emission. This is why electrons are emitted only when the frequency (or energy) of the incident radiation is greater than a certain value.