The frequency of monochromatic light incident on an emitting surface is $f$. If the threshold frequency for the surface is $f_0$,then the maximum kinetic energy of the emitted photoelectrons is .......

If the wavelength of incident light is decreased from $4000 \ \mathring{A}$ to $3600 \ \mathring{A}$,then the change in stopping potential will be ............. $V$.

$A$ stream of photons having energy $3 \,eV$ each impinges on a potassium surface. The work function of potassium is $2.3 \,eV$. The emerging photo-electrons are slowed down by a copper plate placed $5 \,mm$ away. If the potential difference between the two metal plates is $1 \,V$,the maximum distance the electrons can move away from the potassium surface before being turned back is .......... $mm$.

When electromagnetic radiation is incident on a metallic surface,the maximum kinetic energy of the photoelectrons depends on .......

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 ratio of the maximum kinetic energy of the photoelectrons emitted in the first case to that in the second case is $3 : K$, then the threshold frequency of the metallic surface is:

Two monochromatic light beams $A$ and $B$ of equal intensity are incident normally on a metallic surface per unit area. Their wavelengths are $\lambda_A$ and $\lambda_B$ respectively. The incident light is effective in ejecting photoelectrons. The ratio of the number of photoelectrons emitted by beam $A$ to that by beam $B$ is: