Light described at a place by the equation `E=(100 V/m) [sin(5xx10^15 s ^(-1) )t +sin (8xx 10^15 s^(-1) )t]` falls on a metal surface having work function 2.0 eV. Calculate the maximum kinetic energy of the photoelectrons.

Explanation

The light contains two different frequencies. The one with larger frequency will case photoelectrons with largest kinetic energy. This larger frequency is
`v=(omega)/(2pi)=(8xx10^(15)s^(-1))/(2pi)`
The maximum kinetic energy of the photoelectron is
`K_(max)=hv-W`
`=(4.14xx10^(15)eV-s)xx((8xx10^(15))/(2pi)s^(-1))-2.0 eV`
`5.27 eV-2.0eV=3.27 eV`.