Question

In a photoelectric effect experiment, the potential difference $V$ that must be maintained between the illuminated surface and the collector so as just to prevent any electron from reaching the collector is determined for different frequencies $f$ of the incident radiation. The graph obtained is as shown. The maximum kinetic energy of the electrons emitted at frequency $f_1$ is

• A. $h{f}_1$
• B. $\frac{V_1}{(f_1-f_0)}$
• C. $h(f_1-f_0)$
• D. $e{V}_1(f_1-f_0)$

Answer 1

The correct option is C $h(f_1-f_0)$

From graph,
Threshold frequency is $f_0$
Work function is $h{f}_0$
Energy associated with frequency $f_1$ is $h{f}_1$
From Einstein's photoelectric effect equation,
$K{E}_{max}=E-\varphi =h{f}_1-h{f}_0$