Question

For photoelectric effect in a metal, the graph of the stopping potential $V_0$ (in volt) versus frequency $v$ (in hertz) of the incident radiation is shown in Fig. The work function of the metal (in $eV$) is

• A. 12.5
• B. 14.5
• C. 16.5
• D. 18.5

Answer 1

Answer: (C)

16.5

The x-intercept$\left(v_0\right)$ gives the frequency below which no photoelectric effect will take place.

Hence, work function is given by:
$W=h{v}_0=6.63\times {10}^{-34}\times 4\times {10}^{15}=26.52\times {10}^{-19}J$
Converting to eV, we get:
$W=16.5eV$