When light of wavelength 250 nm is incident on a metal surface, the stopping potential of the photoelectrons is 1.00 eV. The threshold frequency for the metal surface is

Question

Quizplus · Accepted Answer

The threshold frequency ($f_0$) can be found using the photoelectric equation $hf = \phi + eV$, where $h$ is Planck's constant ($6.626 \times 10^{-34} \, \text{Js}$), $f$ is the frequency of the incident light, $\phi$ is the work function of the metal, and $eV$ is the stopping potential energy in joules ($1 \, \text{eV} = 1.602 \times 10^{-19} \, \text{J}$). First, convert the wavelength of 250 nm to frequency using $c = \lambda f$, where $c = 3 \times 10^8 \, \text{m/s}$ is the speed of light and $\lambda$ is the wavelength. Then, solve for the work function ($\phi$) using the given stopping potential. Finally, calculate the threshold frequency ($f_0$) from the work function. The correct calculation leads to a threshold frequency around $9.59 \times 10^{14} \, \text{Hz}$.

When Light of Wavelength 250 Nm Is Incident on a Metal