Light of frequency $1.5 \nu_0$ (where $\nu_0$ is the threshold frequency) is incident on a photosensitive material. If the frequency is halved and the intensity is doubled,what happens to the photocurrent?

The quantum nature of light is explained by which of the following phenomena?

The figure shows the variation of photocurrent $i$ with anode potential $V$ for three different radiations. Let $I_a, I_b$ and $I_c$ be the intensities and $f_a, f_b$ and $f_c$ be the frequencies for the curves $a, b$ and $c$ respectively. Then

$A$ source of variable potential difference is connected across a photoelectric cell, and the photoelectric current is plotted against the applied potential difference. The graph with the broken line represents the initial curve of current versus applied potential difference. If the frequency of the incident light is increased and its intensity is reduced, which curve now represents the situation?

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:

The cathode of a photocell is changed such that the work function changes from $w_1$ to $w_2$ $(w_2 > w_1)$. If the saturation currents before and after the change are $I_1$ and $I_2$ respectively,and all other conditions (such as incident light intensity and frequency) remain unchanged,then (assuming $h
u > w_2$):