The work function of a metal is 2.5 × 10–19 J.
(a) Find the threshold frequency for photoelectric emission.
(b) If the metal is exposed to a light beam of frequency 6.0 × 1014 Hz, what will be the stopping potential?
Given, work function W0 (Ф) = 2.5×
J
(a)We know that, Wo = hf
Where h is the Planck’s constant,
f is the threshold frequency
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(b) From photoelectric equation, hf =Kmax +Ф
⇒ hf =eVstop +Ф
Where Vstop is the stopping potential,
Ф is the work function,
f is the frequency of light beam,
h is Planck’s constant,
e is the charge on electron
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