Einstein's photoelectric equation
Maximum KE=λhC−ϕ
=10−5
=5eV
Intensity I=tA(Np)λhC⇒tNp=(λhC)IA
and number of electrons per second. =(tNp)×10
=(λhCIA)×101=10×1.6×10−19×1016×10−3×10−4
=1011 per sec
JEE Main 2019 — Physics Modern Physics
A metal plate of area 1×10−4m2 is illuminated by a radiation of intensity 16m2milliW . The work function of the metal is 5eV. The energy of the incident photons is 10eV and only 10 of it produces photo electrons. The number of emitted photo electron per second and their maximum energy, respectively, will be: [1eV=1.6×10−19J]
Held on 10 Jan 2019 · Verified 6 Jul 2026.
1014 and 10eV
1012 and 5eV
1011 and 5eV
1010 and 5eV
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