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Question
If the frequency of incident light falling on a photosensitive material is doubled, then the kinetic energy of the emitted photoelectron will be ______.
Options
same as its initial value
two times its initial value
more than two times its initial value
less than two times its initial value
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Solution
If the frequency of incident light falling on a photosensitive material is doubled, then the kinetic energy of the emitted photoelectron will be more than two times its initial value.
Explanation:
E = W0 + Kmax
⇒ Kmax = E − W0
= hv − W0
⇒ K1 = hv − W0 and
K2 = 2hv − W0
⇒ K2 > 2K1
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