$A$ photoelectric cell is illuminated by a point source of light placed at a distance of $1 \ m$. If the source is moved to a distance of $2 \ m$,then:

$A$ photocell is illuminated by a small bright source placed $d \; m$ away. When the same source of light is placed $\frac{d}{2} \; m$ away,the number of electrons emitted by the photocathode would

Two metallic plates $A$ and $B$,each of area $5 \times 10^{-4} \, m^2$,are placed parallel to each other at a separation of $1 \, cm$. Plate $B$ carries a positive charge of $33.7 \, pC$. $A$ monochromatic beam of light,with photons of energy $5 \, eV$ each,starts falling on plate $A$ at $t = 0$,so that $10^{16}$ photons fall on it per square meter per second. Assume that one photoelectron is emitted for every $10^6$ incident photons. Also assume that all the emitted photoelectrons are collected by plate $B$ and the work function of plate $A$ remains constant at $2 \, eV$. The electric field between the plates at the end of $10 \, seconds$ is:

Which of the following shows the particle nature of light?

The number of photoelectrons emitted for light of a frequency $\nu$ (higher than the threshold frequency $\nu_0$) is proportional to

$A$ caesium photocell,with a steady potential difference of $60 \ V$ across it,is illuminated by a bright point source of light $50 \ cm$ away. When the same light source is placed $1 \ m$ away,the photoelectrons emitted from the cell: