Will photoelectrons be emitted by a copper surface of work function 4.4eV when illuminated by visible light?

Explanation

Threshold wavelength, `lamda_(0)=(12400)/(W_(0))`
Note that in this relation, `W_(0)` is in eV and `lamda_(0)` in `overset(0)A`
`:.lamda_(0)=(12400)/(4.4)=2818Å`
Since the wavelength of visible light (`4000Å-8000Å`) is more than `lamda_(0)` it cannot eject electrons from copper.