Yellow light emitted from a sodium lamp has a wavelength ($\lambda$) of 580 nm, the frequency $\left(\overline{\mathrm{v}}\right)$ of the yellow light is $5.1724\times {10}^x{\mathrm{s}}^{-1}$. The value of x is

$$\begin{gathered} \text{ Wavelength of yellow light }=580 \mathrm{nm}=580\times {10}^{-9} \mathrm{m} \\ \mathrm{c}\text{ (velocity of light) }=3.0\times {10}^8 {\mathrm{ms}}^{-1} \\ \text{Frequency, }\left(\mathrm{v}\right)=\frac{\mathrm{c}}{\mathrm{\lambda }}=\frac{3.0\times {10}^8{\mathrm{ms}}^{-1}}{580\times {10}^{-9}\mathrm{m}} \\ =5.1724\times {10}^{\underset{x}{\underbrace{14}}} {\mathrm{s}}^{-1} \end{gathered}$$