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

If the frequency of incident light in a photoelectric experiment is doubled,then the stopping potential will

Photoelectric effect can be explained by

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 .......

The photoelectric cut-off voltage in a certain experiment is $1.5 \; V$. What is the maximum kinetic energy of photoelectrons emitted?

Light of wavelength $\lambda$ is incident on the surface of a metal having work function $\phi$, causing the emission of electrons. What is the maximum velocity of the emitted electrons? (Given: $c = \text{velocity of light}$, $h = \text{Planck's constant}$, $m = \text{mass of electron}$)