Photoemission of electrons occurs from a metal \((\phi_0=1.96\,\text{eV})\) when light of frequency \(6.4\times10^{14}\,\text{Hz}\) is incident on it. Calculate:
Energy of a photon in the incident light.
Show Hint
For photoelectric-effect problems, it is often convenient to express photon energy directly in electron volts:
\[
E=h\nu.
\]
After finding energy in joules, divide by
\[
1.6\times10^{-19}
\]
to convert it into eV.