Question

The energy required to remove electron from sodium is $2.3$ eV. Does sodium show photoelectric effect for orange light of wavelength $6800\mathring{A}$?

Answer 1

Energy of incident photon $E=\frac{12400}{\lambda \left(in{A}^o\right)}eV$

So $E=\frac{12400}{6800}=1.82eV$

Since the energy of photon is less than the work function of sodium, so sodium does not show photoelectric effect for orange light.