Light of frequency `4 xx 10^(14)Hz` is incident on a metal surface of work function 2.14 eV, resulting in photoemission of electrons. The maximum kinetic energy of the emitted electrons is `[h = 6.63 xx 10^(-34)J-s]`

Options

A. 0.35 eV
B. 0.14 eV
C. 2.14 eV
D. 0 eV

Answer

D

Explanation

Energy of a light photon, `E = hf`
`= 6.63 xx 10^(-34) xx 4 xx 10^(14)`
`= 6.63 xx 4 xx 10^(-20) J`
`=(6.63 xx 4 xx 10^(-20))/(1.6 xx 10^(-19)) eV = 1.65 eV`
As, energy of incident photon is less than the work function of metal, no photo emission will takes place.