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Question
How does one explain the emission of electrons from a photosensitive surface with the help of Einstein’s photoelectric equation?
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Solution 1
Einstein’s Photoelectric equation is
KEmax = hv - hv0
eV0 = h(v - v0)
From above equation
Case - I:
If v > v0 [Emission with K.E.]
If v = v0 [Just emission]
If v < v0 [No emission]
Solution 2
Einstein's photoelectric equation is, K. E = hv - Φ or hv = Φ + K. E.
This equation explains that when a photon of certain energy is incident on a photosensitive surface, a particular amount of energy gets used as a work function to eject electrons from their shells and the rest of the energy is acquired by ejected electrons as their Kinetic energy. The emission of electrons from a photosensitive surface takes place only if the incident energy of photons is greater than the work function.
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Comment on whether it is consistent with Einstein’s theory:
If c is the velocity of light in free space, the correct statements about photon among the following are:
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- The velocity of a photon is c.
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Choose the correct answer from the options given below:
