The magnetic field associated with a light wave is given, at the origin, by $\mathrm{B}=\mathrm{B}_0\left[\sin \left(3.14 \times 10^7\right) \mathrm{ct}+\sin \left(6.28 \times 10^7\right) \mathrm{ct}\right]$. If this light falls on a silver plate having a work function of 4.7 eV , what will be the maximum kinetic energy of the photo electrons?
$\left(\mathrm{c}=3 \times 10^8 \mathrm{~ms}^{-1}, \mathrm{~h}=6.6 \times 10^{-34} \mathrm{~J}-\mathrm{s}\right)$