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Will photoelectrons be emitted from a co...

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

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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.
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