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Question
The minimum frequency for photoelectric effect on metal is 7 × 1014 Hz, Find the work function of the metal.
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Solution
Work function, `phi_0` = hν0
= 6.63 × 10−34 × 7 × 1014
= 4.641 × 10−19 J
RELATED QUESTIONS
Using the values of work function given in the following table, tell which metal will require the highest frequency of incident radiation to generate photocurrent.
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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