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प्रश्न
Light of wavelength 2000 Å falls on a metal surface of work function 4.2 eV.
What is the kinetic energy (in eV) of the fastest electrons emitted from the surface?
उत्तर
λ = 2000 Å = (2000 × 10-10)m
Wo = 4.2eV
h = 6.63 × 10-34 JS
Using Einstein's photoelectric equation
K. E. = (6.2 – 4.2) eV = 2.0 eV
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