Question

Photoelectrons are observed when a metal is illuminated by light with a wavelength less than 388 nm. What is the metal’s work function?

Short answer

Work function of the metal is 3.2 eV

Step-by-step solution

Step 1. It is given that photoelectrons are observed when metal is illuminated by wavelength less than 388 nm. 

We need to find out the work function of the metal.

Step 2. Using the expression of work function.

$$\begin{gathered} E_0=h{f}_0 \\ {f}_0=\frac{c}{{\lambda }_0} \\ {E}_0=\frac{hc}{{\lambda }_0} \\ {E}_0=\frac{6.63\times {10}^{-34}\times 3\times {10}^{8}m/s}{388\times {10}^{-9}m} \\ {E}_0=3.2eV \end{gathered}$$