A sodium metal piece is illuminated with light of wavelength 0.3 `mum`. The work function of sodium is 2.46 eV. For this situation ,mark out the correct statement (s).

Options

A. The maximum kinetic energy of the ejected photoelectrons is 1.68 eV
B. The cut-off wavelength for sodium is 505 nm
C. The minimum photon energy of incident light for photoelectric effect to take place is 2.46 eV
D. All of the above

Answer

D

Explanation

`K_(max)=hv-phi`
`=((6.63xx10^(-34)xx3xx10^(8))/(0.3xx10^(-6)xx1.6xx10^(-19))-2.46)eV`
`=1.68eV`
Cut-off wavelength, `lamda_0=(hc)/(phi)=505nm`
The minimum energy required to eject the photo-electrons is equal to work function.