Threshold Energy and Threshold Frequency

Threshold energy is defined as the minimum energy required just to emit the electron from metal surface . IT is denoted by wo.
Mathematically,Threshold Energy and Threshold FrequencyThreshold frequency is defined as the minimum frequency of light which just emit electron form the metal surface if exposed to metal surface. This indicates that if the frequency of incident light is less than threshold fre3quency i.e. v<v0 no photoelectric effect takes place.