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Question
Choose the correct option.
Polychromatic (containing many different frequencies) radiation is used in an experiment on the photoelectric effect. The stopping potential ______.
Options
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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Solution
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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