question_answer

A beam of electromagnetic radiation of intensity \[6.4\times {{10}^{5}}W/c{{m}^{2}}\] is comprised of wavelength, \[\lambda =310\text{ }nm\]. It falls normally on a metal (work function \[\varphi =2\text{ }eV\]) of surface area of \[1\text{ }c{{m}^{2}}\]. If one in \[{{10}^{3}}\] photons ejects an electron, total number of electrons ejected in 1 s is \[{{10}^{x}}\]. \[(hc=1240\text{ }eVnm,\text{ }1\text{ }eV=1.6\times {{10}^{19}}J)\], then x is _______. [JEE MAIN Held on 07-01-2020 Morning]

Answer:

11.00