Question

The work function for a certain metal is 4.2 eV. Will this metal give photoelectric emission for incident radiation of wavelength 330 nm?

Answer 1

Work function of the metal is $4.2eV;$

Given: $\lambda =330nm$.

The energy of incident photon is given by,

$E=hc/\lambda$

$E=\frac{6.63\times {10}^{-34}\times 3\times {10}^8}{330\times {10}^{-9}}$

$E=6\times {10}^{-19}Jor3.79eV$

E is less than work function.

Hence, no photoelectric emission will take place.