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Question
Work function of aluminium is 4.2 eV. If two photons each of energy 2.5 eV are incident on its surface, will the emission of electrons take place? Justify your answer.
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Solution
Φ0 = 4.2 eV
hv = 2.5 eV
No there will not be emission of electron because photoelectric effect is one photon are electron
phenomenon.
The energy of one photon is less than walk function. So there will be no emission.
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