A light source of wavelength lambdailluminates a metal and ejects photo-electrons with (K.E.)_("max") = 4 eV . Find the value of work function ?

A light source of wavelength lambdailluminates a metal and ejects phot

1.	A light source of wavelength lambdailluminates a metal and ejects photo-electrons with (K.E.)_("max") = 4 eV . Find the value of work function ?
Answer» 1eV 2eV 0.5 eV None of these Solution :Work function `PHI= H upsilon_0` `phi ` for each metal is constant . if incident ENERGY is KNOWN then `phi` can be calculated.