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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 ______.
विकल्प
Will depend on the average wavelength
Will depend on the longest wavelength
Will depend on the shortest wavelength
Does not depend on the wavelength
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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
Photocurrent recorded in the microammeter in an experimental setup of the photoelectric effect vanishes when the retarding potential is more than 0.8 V if the wavelength of incident radiation is 4950 Å. If the source of incident radiation is changed, the stopping potential turns out to be 1.2 V. Find the work function of the cathode material and the wavelength of the second source.
Given the following data for incident wavelength and the stopping potential obtained from an experiment on the photoelectric effect, estimate the value of Planck's constant and the work function of the cathode material. What is the threshold frequency and corresponding wavelength? What is the most likely metal used for emitter?
| Incident wavelength (in Å) | 2536 | 3650 |
| Stopping potential (in V) |
1.95 | 0.5 |
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The maximum velocity of the photoelectron emitted by the metal surface is 'v '. Charge and mass of the photoelectron is denoted by 'e' and 'm' respectively. The stopping potential in volt is ______.
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[Energy of electron in nth orbit = `-13.6/"n"^2` eV ]
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Explain the failure of wave theory of light to account for the observations from experiments on photoelectric effect.
