JEE Mains · Physics · STD 12 - 11. Dual nature of radiation and matter
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 _______.
- A Doubled
- B Quadrupled
- C Zero
- D Halved
Answer & Solution
Correct Answer
(C) Zero
Step-by-step Solution
Detailed explanation
Since \(\frac{\mathrm{f}}{2}<\mathrm{f}_0\) i.e. the incident frequency is less than threshold frequency. Hence there will be no emission of photoelectrons. \(\Rightarrow\) current \(=0\)
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