Given, fi=f0. Now, f=2fi=2f0.
Since 2f0<f0 i.e. the incident frequency is less than threshold frequency. Hence, there will be no emission of photoelectrons.
Therefore, current =0 and no photo electrons will be emitted.
JEE Main 2024 — Physics Modern Physics
In a photoelectric effect experiment a light of frequency 1.5 times the threshold frequency is made to fall on the surface of photosensitive material. Now if the frequency is halved and intensity is doubled, the number of photo electrons emitted will be:
Held on 31 Jan 2024 · Verified 6 Jul 2026.
Doubled
Quadrupled
Zero
Halved
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