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प्रश्न
Choose the correct option.
Polychromatic (containing many different frequencies) radiation is used in an experiment on the photoelectric effect. The stopping potential ______.
पर्याय
Will depend on the average wavelength
Will depend on the longest wavelength
Will depend on the shortest wavelength
Does not depend on the wavelength
उत्तर
Polychromatic (containing many different frequencies) radiation is used in an experiment on the photoelectric effect. The stopping potential will depend on the shortest wavelength.
Explanation:
The photoelectric effect is the phenomenon of emission of the electron when the photon incident on the metallic surfaces.
• The electrons emitted from the metallic surface due to the photoelectric effect are called photoelectrons.
• The rate of emission of photoelectrons depends upon the frequency or wavelength of the incident light.
• When higher frequency or lower wavelength light incident on the metallic surface, more photoelectrons will be emitted giving rise to the photocurrent.
• Stopping potential is the minimum potential required for the prevention of ejection of photoelectrons due to the low wavelength radiations.
• In the case of polychromatic light, the radiation with high frequency and low wavelength will contribute to the ejection of electrons.
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संबंधित प्रश्न
Can microwaves be used in the experiment on photoelectric effect?
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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