Q.Explain how frequency of incident light varies with stopping potential.

Step 1. Keeping intensity fixed, the stopping-potential measurement is repeated for several different frequencies of incident light.

Step 2. Plotting the resulting current-versus-potential curves for increasing frequencies $\nu_1<\nu_2<\nu_3$ shows all curves reaching the same saturation current (since intensity is unchanged), but crossing zero current at progressively more negative stopping potentials as frequency increases -- meaning $V_0$ grows with $\nu$.

Step 3. Plotting stopping potential $V_0$ against frequency $\nu$ directly gives a straight line: below a certain minimum frequency, the threshold frequency $\nu_0$, no photoelectrons are emitted at all and $V_0=0$; above $\nu_0$, $V_0$ rises linearly with $\nu$. …

Describe the straight-line V0-vs-frequency graph, its threshold-frequency intercept, and that different …

• Saying stopping potential is proportional to frequency from zero frequency, ignoring the threshold-f …