Q. In an experiment on photoelectric effect the frequency $f$ of the incident light is plotted against the stopping potential $V_{0}.$ The work function of the photoelectric surface is given by ($e$ is electronic charge)
A) $OB \times e\ in\ eV$
B) $OB$ in $volt$
C) $OA$ in $eV$
D) The slope of the line $AB$
Explanation
(a) Using Einstein’s equation, $V_{0} = \left( \frac{h}{e} \right)v - \frac{W_{0}}{e}$
Comparing this equation with $y = mx + c$
We get intercept on $- V_{0}$ axis $= \frac{W_{0}}{e}$
$\Rightarrow OB = \frac{W_{0}}{e} \Rightarrow W_{0} = OB \times e$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.