Question

The work function of a metal is 4.6eV. The wavelength of incident light required to emit photo-electrons of zero energy from its surface, will be

• A. 5000 $A^0$
• B. 3100 $A^0$
• C. 1700 $A^0$
• D. 2700 $A^0$

Answer 1

The correct option is D 2700 $A^0$

$E=\frac{hc}{\lambda }$

$4.6eV=\frac{1240eV}{\lambda }$

$\lambda =2700A^0$