The variation of photoelectric current with anode potential is shown below. Choose the correct option ($V_0$ = stopping potential).

If the frequency of incident radiation is kept constant and the experiment is repeated by using incident light of different intensities,then the stopping potential $(V_{s})$

In the photoelectric effect,electrons are emitted from a metal surface only when the incident light has a certain minimum . . . . . . .

The figure shows the variation of photocurrent with anode potential for four different radiations. Let $I_a, I_b, I_c$ and $I_d$ be the intensities for the curves $a, b, c$ and $d$ respectively $[f_a, f_b, f_c$ and $f_d$ are frequencies respectively].

$A$ point source of light is used in an experiment of photoelectric effect. If the distance between the source and the photoelectric surface is doubled, which of the following may result?

Threshold wavelength for photoelectric emission from a metal surface is $5200\,\mathring{A}$. Photoelectrons will be emitted when this surface is illuminated with monochromatic radiation from: