21mv2=eVo=1.68eV⇒hv=λhc=400 nm1240evnm=3.1eV⇒3.1eV=W0+1.6eV∴W0=1.42eV
JEE Main 2009 — Physics Modern Physics
The surface of a metal is illuminated with the light of 400 nm. The kinetic energy of the ejected photoelectrons was found to be 1.68eV. The work function of the metal is (hc=1240eVnm)
Held on 30 Apr 2009 · Verified 6 Jul 2026.
3.09eV
1.41eV
151eV
1.68eV
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