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प्रश्न
Find the kinetic energy of the emitted electron, if in photoelectric effect energy of incident Photon is 4 eV and work function is 2.4 eV.
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उत्तर
K.E.max = hν − φ0
= 4 − 2.4
= 1.6 eV.
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संबंधित प्रश्न
Choose the correct option.
Polychromatic (containing many different frequencies) radiation is used in an experiment on the photoelectric effect. The stopping potential ______.
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 |
The threshold wavelength of tungsten is 2.76 x 10-5 cm.
(a) Explain why no photoelectrons are emitted when the wavelength is more than 2.76 x 10-5 cm.
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(i) if ultraviolet radiation of wavelength λ = 1.80 × 10-5 cm and
(ii) radiation of frequency 4 x 1015 Hz is made incident on the tungsten surface?
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