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In Case of Photo Electric Effect Experiment, Explain the Following Facts, Giving Reasons. the Wave Theory of Light Could Not Explain the Existence of the Threshold Frequency. - Physics

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प्रश्न

In the case of a photo electric effect experiment, explain the following facts, giving reasons.
The wave theory of light could not explain the existence of the threshold frequency.

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उत्तर

If light were strictly a wave, the energy in the light would be represented by the amplitude of the light wave. A more intense light source, even if it were of a lower frequency, would have enough energy to knock out electrons away from the metal surface, which is necessary to generate a photoelectric current.
What actually occurs is that the light below a certain threshold frequency does not generate any current, no matter how intense the light is.

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Photoelectric Effect and Wave Theory of Light
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
2019-2020 (March) Delhi Set 2

संबंधित प्रश्न

Light of frequency 7.21 × 1014 Hz is incident on a metal surface. Electrons with a maximum speed of 6.0 × 105 m/s are ejected from the surface. What is the threshold frequency for photoemission of electrons?


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A photographic film is coated with a silver bromide layer. When light falls on this film, silver bromide molecules dissociate and the film records the light there. A minimum of 0.6 eV is needed to dissociate a silver bromide molecule. Find the maximum wavelength of light that can be recorded by the film.

(Use h = 6.63 × 10-34J-s = 4.14 × 10-15 eV-s, c = 3 × 108 m/s and me = 9.1 × 10-31kg)


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(Use h = 6.63 × 10-34J-s = 4.14 × 10-15 eV-s, c = 3 × 108 m/s and me = 9.1 × 10-31kg)


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Cathode rays can be deflected by


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