Energy of photon. E=310(nm)1240=4eV>2eV (So photoelectric effect will take place)
=4×1.6×10−19=6.4×10−19joule
Number of photons falling per second
=6.4×10−196.4×10−5×1=1014
Number of photoelectron emitted per second
=1031014=1011
A beam of electromagnetic radiation of intensity 6.4×10−5W/cm2 is comprised of wavelength, λ=310nm . It falls normally on a metal (work function ϕ=2eV ) of surface area of 1cm2 . If one in 103 photons ejects an election, total number of electrons ejected in 1s is 10x . (hc=1240eVnm,1eV=1.6×10−19J), then x is ___________
Held on 7 Jan 2020 · Verified 6 Jul 2026.
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