Physics

Problem

The work function of a metal is

2.2\,\text{eV}

. The minimum photon energy required to just eject electrons from its surface is closest to a)

2.20\times10^{-19}\,\text{J}

7.04\times10^{-19}\,\text{J}

3.52\times10^{-19}\,\text{J}

1.38\times10^{-19}\,\text{J}