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प्रश्न
If the frequency of incident light falling on a photosensitive material is doubled, then the kinetic energy of the emitted photoelectron will be ______.
विकल्प
same as its initial value
two times its initial value
more than two times its initial value
less than two times its initial value
उत्तर
If the frequency of incident light falling on a photosensitive material is doubled, then the kinetic energy of the emitted photoelectron will be more than two times its initial value.
Explanation:
E = W0 + Kmax
⇒ Kmax = E − W0
= hv − W0
⇒ K1 = hv − W0 and
K2 = 2hv − W0
⇒ K2 > 2K1
संबंधित प्रश्न
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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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