In photoelectric effect, the energy of the photon striking a metallic surface is `5.6 xx 10^(-19)J`. The kinetic energy of the ejected electrons is `12.0 xx 10^(-20)J`. The work function is:

Options

A. `6.4xx10^(-19)J`
B. `6.8xx10^(-19)J`
C. `4.4xx10^(-19)J`
D. `6.4xx10^(-20)J`

Answer

C

Explanation

Work function `(E_(0))`
KE-Energy of ejected electrons
`(5.6xx10^(-19)-12.0xx10^(-20))J`
`=4.4xx10^(-19)J`.