A beam of electromagnetic radiation of intensity 6.4 × 10^-5 W / cm^2 is comprised of wavelength, λ=310 nm. It falls normally on a metal (work…

A beam of electromagnetic radiation of intensity $\displaystyle 6.4 \times 10^{-5} \mathrm{~W} / \mathrm{cm}^2$ is comprised of wavelength, $\displaystyle \lambda=310 \mathrm{~nm}$. It falls normally on a metal (work function $\displaystyle \varphi=2 \mathrm{eV}$ ) of surface area of $\displaystyle 1 \mathrm{~cm}^2$. If one in $\displaystyle 10^3$ photons ejects an electron, total number of electrons ejected in $\displaystyle 1$ s is $\displaystyle 10^x$. $\displaystyle \left(\mathrm{hc}=1240 \mathrm{eVnm}, 1 \mathrm{eV}=1.6 \times 10^{-19} \mathrm{~J}\right)$, then $\displaystyle x$ is \_\_\_\_.