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प्रश्न
How will you define threshold frequency?
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उत्तर
For a given surface, the emission of photoelectrons takes place only if the frequency of incident light is greater than a certain minimum frequency called the threshold frequency.
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संबंधित प्रश्न
The threshold wavelength for a metal surface whose photoelectric work function is 3.313 eV is __________.
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Give the definition of intensity of light according to quantum concept and its unit.
Define stopping potential.
Briefly discuss the observations of Hertz, Hallwachs and Lenard.
List out the laws of photoelectric effect.
Give the applications photocell.
When a 6000 Å light falls on the cathode of a photo cell, photoemission takes place. If a potential of 0.8 V is required to stop emission of electron, then determine the
- frequency of the light
- energy of the incident photon
- work function of the cathode material
- threshold frequency and
- net energy of the electron after it leaves the surface.
A 3310 Å photon liberates an electron from a material with energy 3 × 10−19 J while another 5000 Å photon ejects an electron with energy 0.972 × 10−19 J from the same material. Determine the value of Planck’s constant and the threshold wavelength of the material.
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