Class 12th Physics 2017 Set1 Delhi Board Paper Solution
How does one explain the emission of electrons from a photosensitive surface with the help of Einstein's photoelectric equation?
According to Einstien’s photoelectric equation, we have
kmax = hf − φ0
Where,
kmax = Maximum kinetic energy of the photoelectrons
φ0 = Work function and
hf = Energy of the incident photon
As, kmax ≥ 0
So, hf − φ0 ≥ 0
or f ≥ φ0 / h
Thus, photoemission occurs, when frequency is greater than threshold frequency, f0 = φ0 / h .
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