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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
Explain the inverse linear dependence of stopping potential on the incident wavelength in a photoelectric effect experiment.
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Typical values of work function for some common metals
| Metal | Work function (in eV) |
| Potassium | 2.3 |
| Sodium | 2.4 |
| Calcium | 2.9 |
| Zinc | 3.6 |
| Silver | 4.3 |
| Aluminium | 4.3 |
| Tungsten | 4.5 |
| Copper | 4.7 |
| Nickel | 5.0 |
| Gold | 5.1 |
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(A) |
(B) |
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(C) |
(D) |
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