When two monochromatic lights of frequency, v and (ν)/2 are incident on a photoelectric metal, their stopping potential becomes (V_s)/2 and V_s…

When two monochromatic lights of frequency, $\displaystyle v$ and $\displaystyle \frac{\nu}{2}$ are incident on a photoelectric metal, their stopping potential becomes $\displaystyle \frac{\mathrm{V}_{\mathrm{s}}}{2}$ and $\displaystyle \mathrm{V}_{\mathrm{s}}$ respectively. The threshold frequency for this metal is :