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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
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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