Question

The work function for a certain metal is 4.2eV. Will this metal give photoelectric emission for incident radiation of wavelength 330 nm? Use, `h=6.6xx10^(-34)Js`.

Answer 1

`v_0=phi_0//h=4.2xx1.6xx10^(-19)//6.6xx10^(-34)`
`=6.72xx10^(15)//6.6Hz`
`v=c//lambda=3xx10^8//330xx10^-9=3xx10^(15)//3.3Hz`
`=6xx10^(15)//6.6Hz`
As `v lt v_0`, therefore no photoelectric emission will take place.