Question

A photon of wavelength 200 $nm$ is incident on metal of work function $\varphi =3eV$, then K.E of emitted photon may have value

• A. 4 $eV$
• B. 3.4 $eV$
• C. 3 $eV$
• D. 6.2 $eV$

Answer 1

The correct option is C 3 $eV$

$K{E}_{max}=\frac{hc}{\lambda }-\varphi =\frac{6.67\times {10}^{-34}\times 3\times {10}^8}{200\times {10}^{-9}\times 1.6\times {10}^{-19}}-3=6.21-3=3.21eVKE<3.21$