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प्रश्न
In a photoelectric experiment, the stopping potential is 1.5V. What is the maximum kinetic energy of a photoelectron?
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उत्तर
Given:
Vs = 1.5 V
To find: Maximum kinetic energy = ?
We know that KEmax = eVs
= 1.6 × 10-19 × 1.5
∴ KE max = 2.4 × 10-19 J
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संबंधित प्रश्न
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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|
(A) |
(B) |
|
(C) |
(D) |
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