The slope of the graph between the frequency of incident light and the stopping potential for a given surface is:

When light of wavelength $\lambda$ incidents on a photosensitive material,photoelectrons are emitted. If the wavelength of the incident light is reduced by $50 \%$,the maximum kinetic energy of the emitted photoelectrons becomes $3$ times the initial maximum kinetic energy. The work function of the material is ($h$ - Planck's constant,$c$ - Speed of light in vacuum).

If the threshold wavelength for sodium is $6800 \mathring{A}$,then the work function will be ............. $eV$.

In an experiment on the photoelectric effect,the frequency $\nu$ of the incident light is plotted against the stopping potential $V_0$. The work function of the photoelectric surface is given by ($e$ is the electronic charge):

Photons of energy $7 \,eV$ are incident on two metals $A$ and $B$ with work functions $6 \,eV$ and $3 \,eV$,respectively. The minimum de-Broglie wavelengths of the emitted photoelectrons with maximum kinetic energies are $\lambda_A$ and $\lambda_B$ respectively,where $\lambda_A / \lambda_B$ is nearly

When light of wavelength $300 \; nm$ falls on a photoelectric emitter,photoelectrons are liberated. For another emitter,light of $600 \; nm$ wavelength is sufficient for creating photoemission. What is the ratio of the work functions of the two emitters?