Monochromatic light of frequency $f$ is incident on an emitter having threshold frequency $f_0$. The maximum kinetic energy of the ejected electron will be

Einstein's photoelectric equation is $E_k = hf - \phi_0$. In this equation,$E_k$ represents ...........

$A$ photoelectric surface is illuminated successively by monochromatic light of wavelength $\lambda$ and $(\lambda/3)$. If the maximum kinetic energy of the emitted photoelectrons in the second case is $4$ times that in the first case, the work function of the surface of the material is ($h$ = Planck's constant, $c$ = speed of light).

The surface of a metal is illuminated with light of $400 \ nm$. The kinetic energy of the ejected photoelectrons was found to be $1.68 \ eV$. The work function of the metal is ............ $eV$ $(hc = 1240 \ eV \ nm)$.

The figure shows different graphs between stopping potential $(V_0)$ and frequency $(\nu)$ for photosensitive surfaces of cesium,potassium,sodium,and lithium. The plots are parallel. The correct ranking of the targets according to their work function,with the greatest first,is:

The work function of Cesium is $2.27 eV$. The cut-off voltage which stops the emission of electrons from a cesium cathode irradiated with light of $600 nm$ wavelength is