NEET Questions Solved


The work function of metal is 1 eV. Light of wavelength 3000 Å is incident on this metal surface. The velocity of emitted photo-electrons will be
(a) 10 m/sec                           (b) 1×103 m/sec
(c) 1×104 m/sec                     (d) 1×106 m/sec

(d) 

E=W0+Kmax;  E=123753000=4.125 eVKmax=E-W0=4.125 eV-1 eV=3.125 eV12mvmax2=3.125×1.6×10-19 Jvmax=2×3.125×1.6×10-199.1×10-31=1×106  m/s

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