The graph of stopping potential $(V_0)$ versus the frequency $(f)$ of incident radiation for the photoelectric effect is ..........

Explain Einstein's photoelectric effect and derive Einstein's photoelectric equation.

The threshold wavelength for photoelectric emission from a material is $5200 \, \mathring{A}$. Photo-electrons will be emitted when this material is illuminated with monochromatic radiation from a

The work functions for sodium and copper are $2 \ eV$ and $4 \ eV$, respectively. Which of them is suitable for a photocell using $4000 \ \mathring{A}$ light?

$A$ beam of light of wavelength $\lambda$ falls on a metal having work function $\phi$ placed in a magnetic field $B$. The most energetic electrons,moving perpendicular to the field,are bent in circular arcs of radius $R$. If the experiment is performed for different values of $\lambda$,then the $B^2$ vs. $\frac{1}{\lambda}$ graph will look like (keeping all other quantities constant):

Photoelectric emission is observed from a metallic surface for frequencies ${\nu _1}$ and ${\nu _2}$ of the incident light rays $({\nu _1} > {\nu _2})$. If the maximum values of kinetic energy of the photoelectrons emitted in the two cases are in the ratio of $1:k$,then the threshold frequency of the metallic surface is