In an experiment on photoelectric emission from a metallic surface, wavelength of incident light is $2…
In an experiment on photoelectric emission from a metallic surface, wavelength of incident light is $2 \times 10^{-7} \mathrm{~m}$ and stopping potential is $2.5 \mathrm{~V}$. The threshold frequency of the metal (in $\mathrm{Hz}$ ) approximately (charge of electron $e=1.6 \times 10^{-19} \mathrm{C}$, Planck's constant $\left.h=6.6 \times 10^{-34} \mathrm{~J}-\mathrm{s}\right)$