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Question
Is it always necessary to use red light to get a photoelectric effect?
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Solution
No, the broad wavelength and low energy of red light, photons do not have sufficient energy to pull an electron out of its orbital.
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RELATED QUESTIONS
If the frequency of incident light falling on a photosensitive material is doubled, then the kinetic energy of the emitted photoelectron will be ______.
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| Incident wavelength (in Å) | 2536 | 3650 |
| Stopping potential (in V) |
1.95 | 0.5 |
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|
(A) |
(B) |
|
(C) |
(D) |
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